sympathetic division of the autonomic nervous system subdivided into central and peripheral parts. The central part of the sympathetic nervous system includes suprasegmental and segmental centers.

Nadsegmental centers are determined in the cerebral cortex, basal ganglia, limbic system, hypothalamus, reticular formation, cerebellum.

Central segmental centers - in the lateral intermediate nuclei of the lateral horns spinal cord, ranging from C VIII to L II segments.

The peripheral part of the sympathetic nervous system includes vegetative nodes of the I and II order.

Nodes of the first order (paravertebral or paravertebral), there are 20-25 pairs of them, they form a sympathetic trunk.

Nodes of the second order (prevertebral) - celiac, superior mesenteric, aorto-renal.

In the sympathetic (Fig. 18) trunk, there are: cervical, thoracic, lumbar, sacral, coccygeal sections.

The cervical region of the sympathetic trunk is represented by 3 nodes: upper, middle and lower, as well as their internodal branches.

The autonomic nerves that come from the sympathetic trunk are sent to the blood vessels, as well as to the organs of the head and neck.

Sympathetic nerves form plexuses around the carotid and vertebral arteries.

Along the course of the arteries of the same name, these plexuses are sent to the cranial cavity, where they give branches to the vessels, the meninges of the brain and the pituitary gland.

From the carotid plexus, fibers go to the lacrimal, sweat, salivary glands, to the muscle that dilates the pupil, to the ear and submandibular nodes.

The organs of the neck receive sympathetic innervation through the laryngeal-pharyngeal plexus. from all three cervical nodes.

From each of the cervical nodes in the direction of the chest cavity depart the upper, middle and lower cardiac nerves, involved in the formation of the heart plexus.

In the thoracic region of the sympathetic trunk, there are up to 10-12 nodes. From 2 to 5 thoracic nodes depart the thoracic cardiac branches involved in the formation of the cardiac plexus.

Thin sympathetic nerves also depart from the thoracic nodes to the esophagus, lungs, thoracic aorta, forming the esophageal, pulmonary, and thoracic aortic plexus.

From the fifth to the ninth thoracic node departs a large splanchnic nerve, and from 10 and 11 - a small splanchnic nerve. Both nerves contain mainly preganglionic fibers that transit through the sympathetic nodes. Through the diaphragm, these nerves enter the abdominal cavity and end at the neurons of the celiac (solar) plexus.

from the solar plexus postganglionic fibers go to the vessels, stomach, intestines and other organs abdominal cavity.

The lumbar sympathetic trunk consists of 3-4 nodes. Branches depart from them to the largest visceral plexus - solar, as well as to the abdominal aortic plexus.

The sacral section of the sympathetic trunk is represented by 3-4 nodes, from which sympathetic nerves depart to the organs of the small pelvis (Fig. 18).

Rice. 18. The structure of the sympathetic division of the autonomic nervous system (S.V. Saveliev, 2008)

parasympathetic nervous system

In the parasympathetic nervous system, there are three foci of exit of fibers from the substance of the brain and spinal cord: mesencephalic, bulbar and sacral.

Parasympathetic fibers are usually components of the spinal or cranial nerves.

Parasympathetic ganglia are located in the immediate vicinity of the innervated organs or in themselves.

The parasympathetic division of the autonomic nervous system is divided into central and peripheral parts. The central part of the parasympathetic nervous system includes suprasegmental and segmental centers.

The central (cranial) section is represented by nuclei III, VII, IX, X pairs of cranial nerves and parasympathetic nuclei of the sacral segments of the spinal cord.

The peripheral section includes: preganglionic fibers in the composition of the cranial nerves and sacral spinal nerves (S 2 -S 4), cranial autonomic nodes, organ plexuses, postganglionic plexuses ending on the working organs.

In the parasympathetic nervous system, the following vegetative nodes are distinguished: ciliary, pterygopalatine, submandibular, sublingual, ear (Fig. 19).

The ciliary node is located in the eye socket. Its size is 1.5-2mm. Preganglionic fibers go to it from the nucleus of Yakubovich (III pair), postganglionic - as part of the ciliary nerves to the muscle that narrows the pupil.

Ear knot, 3-4 mm in diameter, located in the region of the outer base of the skull near the foramen ovale. Preganglionic fibers come to it from the lower salivary nucleus and as part of the glossopharyngeal, and then the tympanic nerves. The latter penetrates into the tympanic cavity, forming the tympanic plexus, from which a small stony nerve is formed, containing preganglionic fibers to the ear node.

Postganglionic fibers (axons of parasympathetic neurons of the ear node) go to the parotid gland as part of the ear-temporal nerve.

Pterygopalatine node (4-5 mm ) located in the pit of the same name.

The preganglionic fibers go to the pterygopalatine ganglion from the superior salivary nucleus, located in the operculum of the bridge, as part of the facial nerve (intermediate). in the channel temporal bone the large stony nerve departs from the facial nerve, it connects with the deep stony nerve (sympathetic), forming the nerve of the pterygoid canal.

After leaving the pyramid of the temporal bone, this nerve enters the pterygopalatine fossa and comes into contact with the neurons of the pterygopalatine ganglion. Postganglionic fibers come from the pterygopalatine ganglion, join the maxillary nerve, innervating the mucous membrane of the nose, palate, and pharynx.

Part of the preganglionic parasympathetic fibers from the superior salivary nucleus, which are not included in the large stony nerve, form a string tympani. The drum string emerges from the pyramid of the temporal bone, joins the lingual nerve and, in its composition, goes to the submandibular and hyoid nodes, from which postganglionic fibers begin to the salivary glands.

Nervus vagus - the main collector of parasympathetic nerve pathways. Preganglionic fibers from the dorsal nucleus vagus nerve go along the numerous branches of the vagus nerve to the organs of the neck, chest and abdominal cavities. They end on the neurons of the parasympathetic ganglions, periorganic and intraorganic autonomic plexuses.

For parenchymal organs, these nodes are near-organ or intraorgan, for hollow organs - intramural.

The sacral part of the parasympathetic nervous system is represented by pelvic ganglions scattered throughout the visceral plexuses of the pelvis. Preganglionic fibers originate from the sacral parasympathetic nuclei of the II-IV sacral segments of the spinal cord, exit them as part of the anterior roots of the spinal nerves and branch off from them in the form of pelvic splanchnic nerves. They form a plexus around the pelvic organs (straight and sigmoid colon, uterus, fallopian tubes, vas deferens, prostate, seminal vesicles).

In addition to the sympathetic and parasympathetic nervous systems, the existence of a metasympathetic nervous system has been proven. It is represented by nerve plexuses and microscopic nodes in the walls of hollow organs with motor skills (stomach, small and large intestines, bladder etc.). These formations differ from parasympathetic mediators (purine bases, peptides, gamma-aminobutyric acid). Nerve cells of metasympathetic nodes are capable of generating nerve impulses without the participation of the central nervous system and sending them to smooth myocytes, causing movement of the organ wall or its part.

Rice. 19. The structure of the parasympathetic division of the autonomic nervous system (S.V. Saveliev, 2008)

Under The term sympathetic nervous system means certain segment (department) autonomic nervous system. Its structure is characterized by some segmentation. This department belongs to the trophic. Its task is to supply organs nutrients, if necessary, increase the rate of oxidative processes, improve breathing, create conditions for the supply of more oxygen to the muscles. In addition, an important task is to accelerate, if necessary, the work of the heart.

Lecture for doctors "Sympathetic nervous system". The autonomic nervous system is divided into sympathetic and parasympathetic parts. The sympathetic part of the nervous system includes:

• lateral intermediate in the lateral columns of the spinal cord;
• sympathetic nerve fibers and nerves running from the cells of the lateral intermediate substance to the nodes of the sympathetic and autonomic plexuses of the abdominal cavity of the pelvis;
• sympathetic trunk, connecting nerves connecting the spinal nerves with the sympathetic trunk;
• nodes of vegetative nerve plexuses;
• nerves from these plexuses to the organs;
• sympathetic fibers.

AUTONOMIC SYSTEM

The vegetative (autonomous) nervous system regulates all the internal processes of the body: the functions of internal organs and systems, glands, circulatory and lymphatic vessels, smooth and partially striated muscles, sensory organs (Fig. 6.1). It provides homeostasis of the body, i.e. the relative dynamic constancy of the internal environment and the stability of its basic physiological functions (blood circulation, respiration, digestion, thermoregulation, metabolism, excretion, reproduction, etc.). In addition, the autonomic nervous system performs an adaptive-trophic function - the regulation of metabolism in relation to environmental conditions.

The term "autonomic nervous system" reflects the control of the involuntary functions of the body. The autonomic nervous system is dependent on the higher centers of the nervous system. There is a close anatomical and functional relationship between the autonomic and somatic parts of the nervous system. Autonomic nerve conductors pass through the cranial and spinal nerves. The main morphological unit of the autonomic nervous system, as well as the somatic one, is the neuron, and the main functional unit is the reflex arc. In the autonomic nervous system, there are central (cells and fibers located in the brain and spinal cord) and peripheral (all its other formations) sections. There are also sympathetic and parasympathetic parts. Their main difference lies in the features of functional innervation and is determined by the attitude to the means that affect the autonomic nervous system. The sympathetic part is excited by adrenaline, and the parasympathetic part by acetylcholine. Ergotamine has an inhibitory effect on the sympathetic part, and atropine on the parasympathetic part.

6.1. Sympathetic division of the autonomic nervous system

Central formations are located in the cerebral cortex, hypothalamic nuclei, brain stem, in the reticular formation, and also in the spinal cord (in the lateral horns). The cortical representation is not sufficiently elucidated. From the cells of the lateral horns of the spinal cord at the level from C VIII to L V, peripheral formations of the sympathetic division begin. The axons of these cells pass as part of the anterior roots and, having separated from them, form a connecting branch that approaches the nodes of the sympathetic trunk. This is where part of the fibers ends. From the cells of the nodes of the sympathetic trunk, the axons of the second neurons begin, which again approach the spinal nerves and end in the corresponding segments. The fibers that pass through the nodes of the sympathetic trunk, without interruption, approach the intermediate nodes located between the innervated organ and the spinal cord. From the intermediate nodes, the axons of the second neurons begin, heading to the innervated organs.

Rice. 6.1.

1 - cortex of the frontal lobe of the brain; 2 - hypothalamus; 3 - ciliary knot; 4 - pterygopalatine node; 5 - submandibular and sublingual nodes; 6- ear knot; 7 - upper cervical sympathetic node; 8 - large splanchnic nerve; 9 - internal node; 10 - celiac plexus; 11 - celiac nodes; 12 - small splanchnic nerve; 12a - lower splanchnic nerve; 13 - superior mesenteric plexus; 14 - lower mesenteric plexus; 15 - aortic plexus; 16 - sympathetic fibers to the anterior branches of the lumbar and sacral nerves for leg vessels; 17 - pelvic nerve; 18 - hypogastric plexus; 19 - ciliary muscle; 20 - sphincter of the pupil; 21 - pupil dilator; 22 - lacrimal gland; 23 - glands of the mucous membrane of the nasal cavity; 24 - submandibular gland; 25 - sublingual gland; 26 - parotid gland; 27 - heart; 28 - thyroid gland; 29 - larynx; 30 - muscles of the trachea and bronchi; 31 - lung; 32 - stomach; 33 - liver; 34 - pancreas; 35 - adrenal gland; 36 - spleen; 37 - kidney; 38 - large intestine; 39- small intestine; 40 - bladder detrusor (muscle that ejects urine); 41 - sphincter of the bladder; 42 - gonads; 43 - genitals; III, XIII, IX, X - cranial nerves

The sympathetic trunk is located along the lateral surface of the spine and has 24 pairs of sympathetic nodes: 3 cervical, 12 thoracic, 5 lumbar, 4 sacral. From the axons of the cells of the upper cervical sympathetic ganglion, the sympathetic plexus of the carotid artery is formed, from the lower - the upper cardiac nerve, which forms the sympathetic plexus in the heart. The aorta, lungs, bronchi, abdominal organs are innervated from the thoracic nodes, and the pelvic organs are innervated from the lumbar nodes.

6.2. Parasympathetic division of the autonomic nervous system

Its formations start from the cerebral cortex, although the cortical representation, as well as the sympathetic part, has not been sufficiently elucidated (mainly it is the limbic-reticular complex). There are mesencephalic and bulbar sections in the brain and sacral - in the spinal cord. The mesencephalic section includes the nuclei of the cranial nerves: the third pair is the accessory nucleus of Yakubovich (paired, small cell), which innervates the muscle that narrows the pupil; Perlia's nucleus (unpaired small cell) innervates the ciliary muscle involved in accommodation. The bulbar section consists of the upper and lower salivary nuclei (VII and IX pairs); X pair - the vegetative nucleus that innervates the heart, bronchi, gastrointestinal tract,

his digestive glands, other internal organs. The sacral section is represented by cells in segments S II -S IV, the axons of which form the pelvic nerve that innervates the urogenital organs and the rectum (Fig. 6.1).

Under the influence of both the sympathetic and parasympathetic divisions of the autonomic nervous system are all organs, with the exception of blood vessels, sweat glands and the adrenal medulla, which have only sympathetic innervation. The parasympathetic department is more ancient. As a result of its activity, stable states of organs and conditions for creating reserves of energy substrates are created. The sympathetic part changes these states (i.e., the functional abilities of organs) in relation to the function being performed. Both parts work in close cooperation. Under certain conditions, the functional predominance of one part over the other is possible. In the case of the predominance of the tone of the parasympathetic part, a state of parasympathotonia develops, the sympathetic part - sympathotonia. Parasympathotonia is characteristic of the state of sleep, sympathotonia - for affective states(fear, anger, etc.).

In clinical conditions, conditions are possible in which the activity of individual organs or body systems is disrupted as a result of the predominance of the tone of one of the parts of the autonomic nervous system. Parasympathetic manifestations accompany bronchial asthma, urticaria, angioedema, vasomotor rhinitis, seasickness; sympathotonic - vasospasm in the form of Raynaud's syndrome, migraine, transient form hypertension, vascular crises in hypothalamic syndrome, ganglionic lesions, panic attacks. The integration of vegetative and somatic functions is carried out by the cerebral cortex, the hypothalamus and the reticular formation.

6.3. Limbico-reticular complex

All activity of the autonomic nervous system is controlled and regulated by the cortical parts of the nervous system (frontal cortex, parahippocampal and cingulate gyrus). The limbic system is the center of emotion regulation and the neural substrate of long-term memory. The rhythm of sleep and wakefulness is also regulated by the limbic system.

Rice. 6.2. limbic system. 1 - corpus callosum; 2 - vault; 3 - belt; 4 - posterior thalamus; 5 - isthmus of the cingulate gyrus; 6 - III ventricle; 7 - mastoid body; 8 - bridge; 9 - lower longitudinal beam; 10 - border; 11 - gyrus of the hippocampus; 12 - hook; 13 - orbital surface of the frontal pole; 14 - hook-shaped bundle; 15 - transverse connection of the amygdala; 16 - front spike; 17 - anterior thalamus; 18 - cingulate gyrus

The limbic system (Fig. 6.2) is understood as a number of closely interconnected cortical and subcortical structures that have common development and functions. It also includes the formation of the olfactory pathways located at the base of the brain, the transparent septum, the vaulted gyrus, the cortex of the posterior orbital surface of the frontal lobe, the hippocampus, and the dentate gyrus. The subcortical structures of the limbic system include the caudate nucleus, the putamen, the amygdala, the anterior tubercle of the thalamus, the hypothalamus, and the nucleus of the frenulum. The limbic system includes a complex interweaving of ascending and descending pathways, closely associated with the reticular formation.

Irritation of the limbic system leads to the mobilization of both sympathetic and parasympathetic mechanisms, which has corresponding vegetative manifestations. A pronounced vegetative effect occurs when the anterior parts of the limbic system are irritated, in particular the orbital cortex, amygdala and cingulate gyrus. At the same time, there are changes in salivation, respiratory rate, increased intestinal motility, urination, defecation, etc.

Of particular importance in the functioning of the autonomic nervous system is the hypothalamus, which regulates the functions of the sympathetic and parasympathetic systems. In addition, the hypothalamus implements the interaction of nervous and endocrine, the integration of somatic and autonomic activity. The hypothalamus contains specific and nonspecific nuclei. Specific nuclei produce hormones (vasopressin, oxytocin) and releasing factors that regulate the secretion of hormones from the anterior pituitary gland.

Sympathetic fibers that innervate the face, head and neck originate from cells located in the lateral horns of the spinal cord (C VIII -Th III). Most of the fibers are interrupted in the superior cervical sympathetic ganglion, and a smaller part goes to the external and internal carotid arteries and forms periarterial sympathetic plexuses on them. They are joined by postganglionic fibers coming from the middle and lower cervical sympathetic nodes. In small nodules (cell clusters) located in the periarterial plexuses of the branches of the external carotid artery, fibers terminate that are not interrupted at the nodes of the sympathetic trunk. The remaining fibers are interrupted in the facial ganglia: ciliary, pterygopalatine, sublingual, submandibular and auricular. Postganglionic fibers from these nodes, as well as fibers from the cells of the upper and other cervical sympathetic nodes, go to the tissues of the face and head, partly as part of the cranial nerves (Fig. 6.3).

Afferent sympathetic fibers from the head and neck are sent to the periarterial plexuses of the branches of the common carotid artery, pass through the cervical nodes of the sympathetic trunk, partially contacting their cells, and through the connecting branches they approach the spinal nodes, closing the arc of the reflex.

Parasympathetic fibers are formed by axons of the stem parasympathetic nuclei, they are directed mainly to the five autonomic ganglia of the face, in which they are interrupted. A smaller part of the fibers goes to the parasympathetic clusters of cells of the periarterial plexuses, where it is also interrupted, and the postganglionic fibers go as part of the cranial nerves or periarterial plexuses. In the parasympathetic part there are also afferent fibers that go in the vagus nerve system and are sent to the sensory nuclei of the brainstem. front and middle departments hypothalamic region through sympathetic and parasympathetic conductors affect the function of predominantly ipsilateral salivary glands.

6.5. Autonomic innervation of the eye

sympathetic innervation. Sympathetic neurons are located in the lateral horns of segments C VIII -Th III of the spinal cord. (centrun ciliospinale).

Rice. 6.3.

1 - posterior central nucleus of the oculomotor nerve; 2 - accessory nucleus of the oculomotor nerve (nucleus of Yakubovich-Edinger-Westphal); 3 - oculomotor nerve; 4 - nasociliary branch from the optic nerve; 5 - ciliary knot; 6 - short ciliary nerves; 7 - sphincter of the pupil; 8 - pupil dilator; 9 - ciliary muscle; 10 - internal carotid artery; 11 - carotid plexus; 12 - deep stony nerve; 13 - upper salivary nucleus; 14 - intermediate nerve; 15 - knee assembly; 16 - large stony nerve; 17 - pterygopalatine node; eighteen - maxillary nerve(II branch of the trigeminal nerve); 19 - zygomatic nerve; 20 - lacrimal gland; 21 - mucous membranes of the nose and palate; 22 - knee-tympanic nerve; 23 - ear-temporal nerve; 24 - middle meningeal artery; 25 - parotid gland; 26 - ear knot; 27 - small stony nerve; 28 - tympanic plexus; 29- auditory tube; 30 - single way; 31 - lower salivary nucleus; 32 - drum string; 33 - tympanic nerve; 34 - lingual nerve (from the mandibular nerve - III branch of the trigeminal nerve); 35 - taste fibers to the anterior 2/3 of the tongue; 36 - sublingual gland; 37 - submandibular gland; 38 - submandibular node; 39 - facial artery; 40 - upper cervical sympathetic node; 41 - cells of the lateral horn ThI-ThII; 42 - the lower node of the glossopharyngeal nerve; 43 - sympathetic fibers to the plexuses of the internal carotid and middle meningeal arteries; 44 - innervation of the face and scalp. III, VII, IX - cranial nerves. in green parasympathetic fibers are marked, red - sympathetic, blue - sensitive

The processes of these neurons, forming preganglionic fibers, exit the spinal cord together with the anterior roots, enter the sympathetic trunk as part of the white connecting branches and, without interruption, pass through the overlying nodes, ending at the cells of the superior cervical sympathetic plexus. The postganglionic fibers of this node accompany the internal carotid artery, braiding its wall, penetrate into the cranial cavity, where they connect with the I branch of the trigeminal nerve, penetrate the orbital cavity and end at the muscle that dilates the pupil (m. dilatator pupillae).

Sympathetic fibers also innervate other structures of the eye: tarsal muscles, which expand the palpebral fissure, the orbital muscle of the eye, as well as some structures of the face - sweat glands of the face, smooth muscles of the face and blood vessels.

parasympathetic innervation. The preganglionic parasympathetic neuron lies in the accessory nucleus of the oculomotor nerve. As part of the latter, it leaves the brain stem and reaches the ciliary ganglion (ganglion ciliare), where it switches to postganglionic cells. From there, part of the fibers goes to the muscle that narrows the pupil (m. sphincter pupillae), and the other part is involved in providing accommodation.

Violation of the autonomic innervation of the eye. The defeat of sympathetic formations causes the Bernard-Horner syndrome (Fig. 6.4) with pupil constriction (miosis), constriction palpebral fissure(ptosis), retraction of the eyeball (enophthalmos). It is also possible to develop homolateral anhidrosis, conjunctival hyperemia, depigmentation of the iris.

The development of the Bernard-Horner syndrome is possible with the localization of the lesion at a different level - the involvement of the posterior longitudinal bundle, the paths to the muscle that dilates the pupil. The congenital variant of the syndrome is more often associated with birth trauma with damage to the brachial plexus.

When the sympathetic fibers are irritated, a syndrome occurs that is the opposite of the Bernard-Horner syndrome (Pourfour du Petit) - expansion of the palpebral fissure and pupil (mydriasis), exophthalmos.

6.6. Vegetative innervation of the bladder

The regulation of the activity of the bladder is carried out by the sympathetic and parasympathetic divisions of the autonomic nervous system (Fig. 6.5) and includes retention of urine and emptying of the bladder. Normally, retention mechanisms are more activated, which

Rice. 6.4. Right-sided Bernard-Horner syndrome. Ptosis, miosis, enophthalmos

is carried out as a result of activation of sympathetic innervation and blockade of the parasympathetic signal at the level of segments L I -L II of the spinal cord, while detrusor activity is suppressed and the tone of the muscles of the internal sphincter of the bladder increases.

Regulation of the act of urination occurs when activated

parasympathetic center at the level of S II -S IV and the center of urination in the bridge of the brain (Fig. 6.6). Descending efferent signals send signals that provide relaxation of the external sphincter, suppress sympathetic activity, remove the block of conduction along parasympathetic fibers, and stimulate the parasympathetic center. This results in contraction of the detrusor and relaxation of the sphincters. This mechanism is under the control of the cerebral cortex; the reticular formation, the limbic system, and the frontal lobes of the cerebral hemispheres take part in the regulation.

Arbitrary stop of urination occurs when a command is received from the cerebral cortex to the centers of urination in the brain stem and sacral spinal cord, which leads to a contraction of the external and internal sphincters of the pelvic floor muscles and periurethral striated muscles.

The defeat of the parasympathetic centers of the sacral region, the autonomic nerves emanating from it, is accompanied by the development of urinary retention. It can also occur when the spinal cord is damaged (trauma, tumor, etc.) at a level above the sympathetic centers (Th XI -L II). Partial damage to the spinal cord above the level of the location of the autonomic centers can lead to the development of an imperative urge to urinate. When the spinal sympathetic center (Th XI - L II) is affected, true urinary incontinence occurs.

Research methodology. There are numerous clinical and laboratory methods for studying the autonomic nervous system, their choice is determined by the task and conditions of the study. However, in all cases, it is necessary to take into account the initial vegetative tone and the level of fluctuations relative to the background value. The higher the baseline, the lower will be the response in functional tests. In some cases, even a paradoxical reaction is possible. Beam study

Rice. 6.5.

1 - cerebral cortex; 2 - fibers that provide arbitrary control over the emptying of the bladder; 3 - fibers of pain and temperature sensitivity; 4 - cross section of the spinal cord (Th IX -L II for sensory fibers, Th XI -L II for motor); 5 - sympathetic chain (Th XI -L II); 6 - sympathetic chain (Th IX -L II); 7 - cross section of the spinal cord (segments S II -S IV); 8 - sacral (unpaired) node; 9 - genital plexus; 10 - pelvic splanchnic nerves;

11 - hypogastric nerve; 12 - lower hypogastric plexus; 13 - genital nerve; 14 - external sphincter of the bladder; 15 - bladder detrusor; 16 - internal sphincter of the bladder

Rice. 6.6.

it is better to do it in the morning on an empty stomach or 2 hours after eating, at the same time, at least 3 times. The minimum value of the received data is taken as the initial value.

Main clinical manifestations the predominance of the sympathetic and parasympathetic systems are presented in Table. 6.1.

To assess the autonomic tone, it is possible to conduct tests with exposure to pharmacological agents or physical factors. As pharmacological agents use solutions of adrenaline, insulin, mezaton, pilocarpine, atropine, histamine, etc.

Cold test. In the supine position, the heart rate is calculated and blood pressure is measured. After that, the other hand is dipped in cold water (4 °C) for 1 min, then the hand is taken out of the water and the blood pressure and pulse are recorded every minute until they return to the initial level. Normally, this happens after 2-3 minutes. With an increase in blood pressure by more than 20 mm Hg. Art. the reaction is considered pronounced sympathetic, less than 10 mm Hg. Art. - moderate sympathetic, and with a decrease in blood pressure - parasympathetic.

Oculocardial reflex (Dagnini-Ashner). When pressed on eyeballs in healthy people, the heart rate slows down by 6-12 per minute. If the number of heart rate decreases by 12-16 per minute, this is regarded as a sharp increase in the tone of the parasympathetic part. The absence of a decrease or increase in heart rate by 2-4 per minute indicates an increase in the excitability of the sympathetic department.

solar reflex. The patient lies on his back, and the examiner presses his hand on the upper abdomen until a pulsation of the abdominal aorta is felt. After 20-30 seconds, the heart rate slows down in healthy people by 4-12 per minute. Changes in cardiac activity are assessed in the same way as when evoking an oculocardial reflex.

orthoclinostatic reflex. In a patient lying on his back, the heart rate is calculated, and then they are asked to stand up quickly (orthostatic test). When moving from a horizontal to a vertical position, the heart rate increases by 12 per minute with an increase in blood pressure by 20 mm Hg. Art. When the patient moves to a horizontal position, the pulse and blood pressure return to their original values ​​within 3 minutes (clinostatic test). The degree of pulse acceleration during an orthostatic test is an indicator of the excitability of the sympathetic division of the autonomic nervous system. A significant slowing of the pulse during the clinostatic test indicates an increase in the excitability of the parasympathetic department.

Table 6.1.

Continuation of table 6.1.

Adrenaline test. At healthy person subcutaneous injection of 1 ml of a 0.1% solution of adrenaline after 10 minutes causes blanching of the skin, increased blood pressure, increased heart rate and increased blood glucose levels. If such changes occur faster and are more pronounced, then the tone of sympathetic innervation is increased.

Skin test with adrenaline. A drop of 0.1% adrenaline solution is applied to the skin injection site with a needle. In a healthy person, blanching with a pink corolla around occurs in such an area.

Atropine test. Subcutaneous injection of 1 ml of a 0.1% solution of atropine in a healthy person causes dry mouth, decreased sweating, increased heart rate and dilated pupils. With an increase in the tone of the parasympathetic part, all reactions to the introduction of atropine are weakened, so the test can be one of the indicators of the state of the parasympathetic part.

To assess the state of the functions of segmental vegetative formations, the following tests can be used.

Dermographism. Mechanical irritation is applied to the skin (with the handle of a hammer, with the blunt end of a pin). The local reaction occurs as an axon reflex. At the site of irritation, a red band appears, the width of which depends on the state of the autonomic nervous system. With an increase in sympathetic tone, the band is white (white dermographism). Wide stripes of red dermographism, a stripe rising above the skin (sublime dermographism), indicate an increase in the tone of the parasympathetic nervous system.

For topical diagnosis, reflex dermographism is used, which is irritated with a sharp object (swiped across the skin with the tip of a needle). There is a strip with uneven scalloped edges. Reflex dermographism is a spinal reflex. It disappears in the corresponding zones of innervation when the posterior roots, segments of the spinal cord, anterior roots and spinal nerves are affected at the level of the lesion, but remains above and below the affected zone.

Pupillary reflexes. Determine the direct and friendly reaction of the pupils to light, the reaction to convergence, accommodation and pain (dilation of the pupils with a prick, pinch and other irritations of any part of the body).

Pilomotor reflex caused by a pinch or by applying a cold object (a test tube with cold water) or coolant (cotton soaked in ether) to the skin of the shoulder girdle or the back of the head. On the same half of the chest, "goosebumps" appear as a result of contraction of smooth hair muscles. The arc of the reflex closes in the lateral horns of the spinal cord, passes through the anterior roots and the sympathetic trunk.

Test with acetylsalicylic acid. After taking 1 g of acetylsalicylic acid, diffuse sweating appears. With the defeat of the hypothalamic region, its asymmetry is possible. With damage to the lateral horns or anterior roots of the spinal cord, sweating is disturbed in the zone of innervation of the affected segments. With damage to the diameter of the spinal cord, taking acetylsalicylic acid causes sweating only above the site of the lesion.

Trial with pilocarpine. The patient is injected subcutaneously with 1 ml of a 1% solution of pilocarpine hydrochloride. As a result of irritation of the postganglionic fibers going to the sweat glands, sweating increases.

It should be borne in mind that pilocarpine excites peripheral M-cholinergic receptors, which cause increased secretion of the digestive and bronchial glands, constriction of the pupils, an increase in the tone of the smooth muscles of the bronchi, intestines, gall and bladder, uterus, but pilocarpine has the strongest effect on sweating. With damage to the lateral horns of the spinal cord or its anterior roots in the corresponding area of ​​the skin, after taking acetylsalicylic acid, sweating does not occur, and the introduction of pilocarpine causes sweating, since the postganglionic fibers that respond to this drug remain intact.

Light bath. Warming the patient causes sweating. This is a spinal reflex similar to the pilomotor reflex. The defeat of the sympathetic trunk completely eliminates sweating after the use of pilocarpine, acetylsalicylic acid and warming the body.

Skin thermometry. Skin temperature is examined using electrothermometers. Skin temperature reflects the state of the blood supply to the skin, which is important indicator autonomic innervation. Areas of hyper-, normo- and hypothermia are determined. The difference in skin temperature of 0.5 °C in symmetrical areas indicates a violation of autonomic innervation.

Electroencephalography is used to study the autonomic nervous system. The method makes it possible to judge the functional state of the synchronizing and desynchronizing systems of the brain during the transition from wakefulness to sleep.

There is a close relationship between the autonomic nervous system and emotional state a person, therefore, they study the psychological status of the subject. To do this, use special sets of psychological tests, the method of experimental psychological testing.

6.7. Clinical manifestations of lesions of the autonomic nervous system

With dysfunction of the autonomic nervous system, various disorders occur. Violations of its regulatory functions are periodic and paroxysmal. Majority pathological processes does not lead to the loss of certain functions, but to irritation, i.e. to increased excitability of central and peripheral structures. On the-

disruption in some parts of the autonomic nervous system can spread to others (repercussion). The nature and severity of symptoms are largely determined by the level of damage to the autonomic nervous system.

Damage to the cerebral cortex, especially the limbic-reticular complex, can lead to the development of vegetative, trophic, emotional disturbances. They may be due infectious diseases, injuries of the nervous system, intoxication. Patients become irritable, quick-tempered, quickly exhausted, they experience hyperhidrosis, instability vascular reactions, fluctuations in blood pressure, pulse. Irritation of the limbic system leads to the development of paroxysms of pronounced vegetative-visceral disorders (cardiac, gastrointestinal, etc.). Psychovegetative disorders are observed, including emotional disorders (anxiety, anxiety, depression, asthenia) and generalized autonomic reactions.

With damage to the hypothalamic region (Fig. 6.7) (tumor, inflammatory processes, circulatory disorders, intoxication, trauma), vegetative-trophic disorders may occur: sleep and wakefulness rhythm disturbances, thermoregulation disorder (hyper- and hypothermia), ulceration in the gastric mucosa, lower esophagus, acute perforation of the esophagus, duodenum and stomach, as well as endocrine disorders: diabetes insipidus, adiposogenital obesity, impotence.

Damage to the vegetative formations of the spinal cord with segmental disorders and disorders localized below the level of the pathological process

Patients may have vasomotor disorders (hypotension), sweating disorders and pelvic functions. With segmental disorders, trophic changes are noted in the relevant areas: increased dryness skin, local hypertrichosis or local hair loss, trophic ulcers and osteoarthropathy.

With the defeat of the nodes of the sympathetic trunk, similar clinical manifestations occur, especially pronounced with the involvement of the cervical nodes. There is a violation of sweating and a disorder of pilomotor reactions, hyperemia and an increase in the temperature of the skin of the face and neck; due to a decrease in the tone of the muscles of the larynx, hoarseness of the voice and even complete aphonia may occur; Bernard-Horner syndrome.

Rice. 6.7.

1 - damage to the lateral zone (increased drowsiness, chills, increased pilomotor reflexes, pupillary constriction, hypothermia, low blood pressure); 2 - damage to the central zone (violation of thermoregulation, hyperthermia); 3 - damage to the supraoptic nucleus (impaired secretion of antidiuretic hormone, diabetes insipidus); 4 - damage to the central nuclei (pulmonary edema and erosion of the stomach); 5 - damage to the paraventricular nucleus (adipsia); 6 - damage to the anteromedial zone (increased appetite and impaired behavioral responses)

The defeat of the peripheral parts of the autonomic nervous system is accompanied by a number of characteristic symptoms. Most often there is a kind of pain syndrome - sympathalgia. The pains are burning, pressing, bursting, tend to gradually spread beyond the area of ​​primary localization. Pain is provoked and aggravated by changes in barometric pressure and temperature environment. Changes in the color of the skin due to spasm or expansion of peripheral vessels are possible: blanching, redness or cyanosis, changes in sweating and skin temperature.

Autonomic disorders can occur with damage to the cranial nerves (especially the trigeminal), as well as the median, sciatic, etc. The defeat of the autonomic ganglia of the face and oral cavity causes burning pains in the zone of innervation related to this ganglion, paroxysmality, hyperemia, increased sweating, in case of damage to the submandibular and sublingual nodes - an increase in salivation.

The article reveals questions about the concept of the sympathetic nervous system, its structure, formation and functions.

Its connection with other parts of the central system is considered, a comparative characteristic of the action of the sympathetic and parasympathetic on the human body is proposed.

General information

The sympathetic nervous system is one of the departments that has a segmental structure. The main role of the autonomic department is to control unconscious actions.

The main function of the sympathetic nervous system is to ensure the body's responses when its internal state remains unchanged.

There are central and peripheral parts of the sympathetic nervous system. The first serves as the main component of the spinal cord, the second is a large number of closely spaced nerve cells.

The center of the sympathetic nervous system is localized to the side of the thoracic and lumbar regions. It processes oxidation, respiration and cardiac activity, thereby preparing the body for intensive work. Therefore, the main time of activity of this nervous system falls on the daytime.

Structure

The central division of the sympathetic system is located to the left and right of the spine. Here originate, responsible for the work of internal organs, most glands, organs of vision. In addition, there are centers responsible for sweating and vasomotor processes. It has been clinically proven that the spinal cord is also involved in metabolic processes and the regulation of body temperature.

Consists of two sympathetic trunks located along the entire spinal column. The composition of each trunk includes nerve nodes, which together form more complex nerve fibers. Each sympathetic trunk is represented by four departments.

The cervical region is found behind the carotid arteries in the depths of the muscles of the neck, it consists of three nodes - upper, middle and lower. The superior cervical ganglion, 1.8 cm in diameter, is located between the second and third cervical vertebrae. The middle node is located between the thyroid and carotid arteries, sometimes it is not detected. The lower cervical node is located at the beginning of the vertebral artery, connecting with the first or second thoracic nodes, forming a common cervicothoracic element. Nerve fibers responsible for cardiac activity and brain function begin from the cervical sympathetic nodes.

The thoracic region is located along the heads of the ribs on both sides of the spine, and is protected by a special opaque dense film. This department is represented by connecting branches and nine nodes of different geometry. Thanks to thoracic The sympathetic trunk supplies the abdominal organs with nerves, as well as the vessels of the chest and abdomen.

The lumbar (abdominal) section of the sympathetic trunk includes four nodes located in front of the lateral surface of the vertebrae. In the abdominal region, the upper visceral nerve cells that form the celiac plexus are distinguished, and the lower ones form the mesenteric plexus. By using lumbar the pancreas and intestines are innervated.

The sacral (pelvic) section is represented by four nodes that are located in front of the coccygeal vertebrae. The pelvic nodes give rise to fibers that form the hypogastric plexus, which consists of several segments. The sacral region innervates the organs of urination, the rectum, male and female gonads.

Functions

Takes part in cardiac activity, regulates the frequency, rhythm and strength of heart beats. Increases the clearance in the respiratory organs - lungs and bronchi. Reduces the motor, secretory and absorption capacity of the digestive organs. Maintains the body in an active state with the constancy of its internal environment. Provides breakdown of glycogen in the liver. Accelerates the work of endocrine glands.

Regulates the processes of metabolism and metabolism, which facilitates adaptation to new environmental conditions. Due to the produced adrenaline and norepinephrine, it helps a person to make decisions quickly in difficult situations. Carries out the innervation of all internal organs and tissues. Participates in strengthening the immune mechanisms of the body, is a stimulant of hormonal reactions.

Reduces the tone of smooth muscle fibers. Increases blood sugar and cholesterol levels. Helps the body get rid of fatty acids and toxic substances. Increases performance blood pressure. Participates in the delivery of oxygen to the blood arteries and vessels.

Provides the flow of nerve impulses throughout the entire spinal column. Participates in the process of dilating the pupils of the eyes. Brings to a state of excitation all the centers of sensitivity. Releases the stress hormones adrenaline and norepinephrine into the blood vessels. Increases sweating during exercise. Slows down the formation of saliva.

How is formed

Initiation begins in the ectoderm. The main inclusions are formed in the spine, hypothalamus, brain stem. Peripheral inclusions originate in the lateral vertebrae of the spinal cord. From this moment, connecting branches are formed, suitable for the nodes of the sympathetic system. Already from the third week of embryonic growth, neural trunks and nodes are laid from neuroblasts, which serve as a prerequisite for the subsequent formation of internal organs. Initially, trunks form in the walls of the intestine, then in the tube of the heart.

The trunks of the sympathetic system consist of the following nodes - 3 cervical, 12 thoracic, 5 abdominal and 4 pelvic. From cells cervical node plexuses of the heart and carotid artery are formed. Thoracic nodes start the work of the lungs, blood vessels, bronchi, pancreas, lumbar - are involved in the transmission of nerve reactions to the bladder, male and female genital organs.

The whole process of formation of the sympathetic system takes about four to five months of embryonic growth and fetal development.

Interaction with other departments of the central nervous system

Together with the parasympathetic, it controls the internal activities of the body.

The sympathetic and parasympathetic systems are closely interconnected and work in combination, providing a connection between human organs and the central nervous system.

How these two systems act on the human body is presented in the table:

Name of body, system	sympathetic	Parasympathetic
eye pupil	extension	constriction
salivary glands	a small amount, the structure is thick	profuse watery structure
lacrimal glands	no influence	increases
sweat glands	increases sweating	does not affect
heart	speeds up the rhythm, strengthens contractions	slows down the rhythm, reduces contractions
blood vessels	constriction	little effect
respiratory system	increases the respiratory rate, the lumen expands	slows down breathing, the lumen becomes smaller
adrenal glands	adrenaline is synthesized	not produced
digestive organs	inhibition of activity	increases gastrointestinal tone
bladder	relaxation	reduction
sexual organs	ejaculation	erection
sphincters	activity	braking

Violations in the work of one of the systems can lead to diseases of the respiratory system, musculoskeletal system, heart and blood vessels.

If the sympathetic system predominates, then the following signs of excitability are observed:

• frequent increase in body temperature;
• tingling or numbness of the extremities;
• cardiopalmus;
• increased feeling of hunger;
• restless sleep;
• apathy towards oneself and the life of loved ones;
• severe headaches;
• increased irritability and sensitivity;
• carelessness and distraction.

In the case of increased work of the parasympathetic department, the following symptoms are found:

• skin is pale and cold;
• the frequency and rhythm of heart contractions decrease;
• possible fainting;
• increased fatigue;
• indecision;
• frequent depressive states.

The autonomic nervous system, also called the autonomic nervous system, has several divisions or parts. One of them is sympathetic division into departments based on functional and morphological features. Another subspecies is the parasympathetic nervous system.

In life, the nervous system performs a wide range of functions, which makes it very important. The system itself is complex and has several departments and subspecies, each of which takes on some of the functions. The most interesting thing is that for the first time such a thing as the sympathetic nervous system appeared in 1732. Initially, the term was used to refer to the entire But, as the knowledge of scientists accumulated, they realized that a much more extensive layer was hidden here, so this concept began to be attributed to only one of the subspecies.

If we consider specific values, it turns out that the sympathetic nervous system performs quite interesting functions for the body - it is she who is responsible for the consumption of resources, as well as for the mobilization of forces in emergency situations. If such a need arises, then the sympathetic system increases the expenditure of energy so that the body can continue to function normally and perform its tasks. When we talk about hidden opportunities and resources, that's what we mean. The state of the body will depend on how the system will cope with this.

However, all this is a strong stress for the body, so for a long time in this mode it will not be able to function. Here the parasympathetic system comes into play, whose tasks include the restoration of resources and their accumulation, so that later a person can perform the same tasks, and his capabilities are not limited. Sympathetic and ensure the normal functioning of the human body in different conditions. They work inseparably and constantly complement each other.

anatomical device

The sympathetic nervous system appears to be a fairly complex and branched structure. The central part is located in the spinal cord, and the periphery connects various endings in the body. Actually, the endings of the sympathetic nerves are connected in numerous innervated tissues into plexuses.

The periphery of the system is formed by a variety of sensitive efferent neurons, from which special processes extend. They are removed from the spinal cord and are collected mainly in the prevertebral and paravertebral nodes.

Functions of the sympathetic system

As mentioned earlier, the sympathetic system is fully activated in stressful situations. In some sources, it is called the reactive sympathetic nervous system, because it must give a certain reaction of the body to a situation formed from the outside.

At this point, adrenaline begins to be produced in the adrenal glands, which serves as the main substance that allows a person to better and faster respond to stressful situations. However, a similar situation can also arise when physical activity when, due to the adrenaline rush, a person begins to better cope with it. The secretion of adrenaline enhances the action of the sympathetic system, which begins to "provide" resources for increased energy consumption, because adrenaline only stimulates various organs and senses, but is in no way the resource itself.

The effect on the body is quite high, because after that a person experiences fatigue, fatigue, and so on, depending on how long the adrenaline effect lasted and how long the sympathetic system expended resources to keep the body working at the same level.

The sympathetic division is part of the autonomic nervous tissue, which, together with the parasympathetic, ensures the functioning of internal organs, chemical reactions responsible for the vital activity of cells. But you should know that there is a metasympathetic nervous system, a part of the vegetative structure, located on the walls of organs and capable of contracting, contacting directly with the sympathetic and parasympathetic, making adjustments to their activity.

The internal environment of a person is under the direct influence of the sympathetic and parasympathetic nervous system.

The sympathetic division is located in the central nervous system. Spinal nerve tissue carries out its activities under the control of nerve cells located in the brain.

All elements of the sympathetic trunk, located on two sides from the spine, are directly connected with the corresponding organs through the nerve plexuses, while each has its own plexus. At the bottom of the spine, both trunks in a person are combined together.

The sympathetic trunk is usually divided into sections: lumbar, sacral, cervical, thoracic.

The sympathetic nervous system is concentrated around the carotid arteries cervical, in the chest - cardiac, as well as pulmonary plexus, in the abdominal cavity solar, mesenteric, aortic, hypogastric.

These plexuses are divided into smaller ones, and from them impulses move to the internal organs.

The transition of excitation from the sympathetic nerve to the corresponding organ occurs under the influence of chemical elements - sympathins, secreted by nerve cells.

They supply the same tissues with nerves, ensuring their interconnection, with central system, often having a directly opposite effect on these organs.

The influence exerted by the sympathetic and parasympathetic nervous systems can be seen from the table below:

Together they are responsible for cardiovascular organisms, digestive organs, respiratory structure, excretion, smooth muscle function of hollow organs, control metabolic processes, growth, and reproduction.

If one begins to predominate over the other, symptoms of increased excitability of sympathicotonia appear (predominant sympathetic part), vagotonia (parasympathetic predominates).

Sympathicotonia manifests itself in the following symptoms: fever, tachycardia, numbness and tingling in the limbs, increased appetite without the appearance of being deprived of weight, indifference to life, restless dreams, fear of death for no reason, irritability, absent-mindedness, salivation decreases, as well as sweating, migraine appears.

In humans, when activated increased work parasympathetic division of the vegetative structure are manifested excessive sweating, the skin is cold and wet to the touch, there is a decrease in the heart rate, it becomes less than the prescribed 60 beats per 1 minute, fainting, salivation and respiratory activity increase. People become indecisive, slow, prone to depression, intolerant.

The parasympathetic nervous system reduces the activity of the heart, has the ability to dilate blood vessels.

Functions

The sympathetic nervous system is a unique design of an element of the autonomic system, which, in the event of a sudden need, is able to increase the body's ability to perform work functions by collecting possible resources.

As a result, the design carries out the work of such organs as the heart, reduces blood vessels, increases the ability of muscles, frequency, strength of the heart rhythm, performance, inhibits the secretory, suction capacity of the gastrointestinal tract.

The SNS maintains such functions as the normal functioning of the internal environment in an active position, being activated during physical effort, stressful situations, illness, blood loss, and regulates metabolism, for example, an increase in sugar, blood clotting, and others.

It is most fully activated during psychological upheavals, by producing adrenaline (enhancing the action of nerve cells) in the adrenal glands, which enables a person to respond faster and more efficiently to sudden factors from the outside world.

Adrenaline is also able to be produced with an increase in load, which also helps a person to better cope with it.

After coping with the situation, a person feels tired, he needs to rest, this is due to sympathetic system, which most fully used up the possibilities of the organism, due to an increase in the functions of the organism in a sudden situation.

The parasympathetic nervous system performs the functions of self-regulation, protection of the body, and is responsible for emptying a person.

Self-regulation of the body has a restorative effect, working in a calm state.

The parasympathetic part of the activity of the autonomic nervous system is manifested by a decrease in the strength and frequency of the heart rhythm, stimulation of the gastrointestinal tract with a decrease in glucose in the blood, etc.

Carrying out protective reflexes, it relieves the human body of foreign elements (sneezing, vomiting, and others).

The table below shows how the sympathetic and parasympathetic nervous systems act on the same elements of the body.

Treatment

If you notice signs of increased sensitivity, you should consult a doctor, as this can cause a disease of an ulcerative, hypertensive nature, neurasthenia.

correct and effective therapy only a doctor can prescribe! There is no need to experiment with the body, since the consequences, if the nerves are in a state of excitability, are a rather dangerous manifestation not only for you, but also for people close to you.

When prescribing treatment, it is recommended, if possible, to eliminate factors that excite the sympathetic nervous system, whether it be physical or emotional stress. Without this, no treatment is likely to help, after drinking a course of medicine, you will get sick again.

You need a cozy home environment, sympathy and help from loved ones, Fresh air, good emotions.

First of all, you need to make sure that nothing raises your nerves.

The drugs used in the treatment are basically a group of potent drugs, so they should be used carefully only as directed or after consulting a doctor.

To the appointed medicines usually include: tranquilizers (Phenazepam, Relanium and others), antipsychotics (Frenolone, Sonapax), hypnotics, antidepressants, nootropics medicines and, if necessary, cardiac (Korglikon, Digitoxin), vascular, sedative, vegetative drugs, a course of vitamins.

It is good when using physiotherapy, including physiotherapy exercises and massage, you can do breathing exercises, swimming. They help to relax the body.

In any case, ignoring the treatment this disease It is categorically not recommended, it is necessary to consult a doctor in a timely manner, to conduct the prescribed course of therapy.