The neurons from which preganglionic fibers arise are located in the lateral horns spinal cord at the level Th II -T VI. These fibers approach the superior cervical ganglion (gangl. cervicale superior), where they end on postganglionic neurons that give rise to axons. These postganglionic nerve fibers, together with the choroid plexus accompanying the internal carotid artery (plexus caroticus internus), reach the parotid salivary gland and, as part of the choroid plexus surrounding the external carotid artery (plexus caroticus externus), the submandibular and sublingual salivary glands.

Parasympathetic fibers play main role in the regulation of saliva secretion. Irritation of parasympathetic nerve fibers leads to the formation of acetylcholine in their nerve endings, which stimulates the secretion of glandular cells.

Sympathetic fibers of the salivary glands are adrenergic. Sympathetic secretion has a number of features: the amount of saliva released is significantly less than during irritation of the chorda tympani, saliva is released in rare drops, and it is thick. In humans, stimulation of the sympathetic trunk in the neck causes secretion from the submandibular gland, while no secretion occurs in the parotid gland.

Salivary centers The medulla oblongata consists of two symmetrically located neuronal pools in the reticular formation. The rostral part of this neural formation - the superior salivary nucleus - is connected with the submandibular and sublingual glands ami, the caudal part - the lower salivary nucleus - with the parotid gland. Stimulation in the area located between these nuclei causes secretion from the submandibular and parotid glands.

The diencephalic region plays an important role in the regulation of salivation. When the anterior hypothalamus or preoptic area (thermoregulation center) is stimulated in animals, the heat loss mechanism is activated: the animal opens its mouth wide, shortness of breath and salivation begin. When the posterior hypothalamus is stimulated, strong emotional arousal and increased salivation occur. Hess (Hess, 1948), when stimulating one of the zones of the hypothalamus, observed a picture of eating behavior, which consisted of movements of the lips, tongue, chewing, salivation and swallowing. The amygdala has close anatomical and functional connections with the hypothalamus. Specifically, stimulation of the amygdala complex causes the following food reactions: licking, sniffing, chewing, salivation and swallowing.

Salivary secretion produced by stimulation of the lateral hypothalamus after removal frontal lobes cerebral cortex increases significantly, which indicates the presence of inhibitory influences of the cerebral cortex on the hypothalamic sections of the salivary center. Salivation can also be caused by electrical stimulation of the olfactory brain (rhinencephalon).

Besides nervous regulation the work of the salivary glands, a certain influence on their activity of sex hormones, hormones of the pituitary gland, pancreas and thyroid glands has been established.

Some chemicals can stimulate or, conversely, inhibit the secretion of saliva, acting either on the peripheral apparatus (synapses, secretory cells) or on nerve centers. Abundant Department saliva is observed during asphyxia. In this case, increased salivation is a consequence of irritation of the salivary centers with carbonic acid.

The influence of some pharmacological substances on the salivary glands is associated with the mechanism of transmission of nervous influences from parasympathetic and sympathetic nerve endings to the secretory cells of the salivary glands. Some of these pharmacological substances (pilocarpine, proserine and others) stimulate salivation, while others (for example, atropine) inhibit or stop it.

Mechanical processes in the oral cavity.

The upper and lower ends of the digestive tract differ from other parts in that they are relatively fixed to the bones and consist not of smooth, but mainly of striated muscle. IN oral cavity food comes in the form of pieces or liquids of varying consistency. Depending on this, it either immediately passes into the next section of the digestive tract, or is subjected to mechanical and initial chemical treatment.

Chewing. The process of mechanical processing of food - chewing - consists of grinding its solid components and mixing with saliva. Chewing also contributes to the assessment of the taste of food and is involved in the stimulation of salivary and gastric secretion. Since chewing mixes food with saliva, it facilitates not only swallowing, but also partial digestion of carbohydrates by amylase.

The act of chewing is partly reflexive, partly voluntary. When food enters the oral cavity, the receptors of its mucous membrane (tactile, temperature, taste) are irritated, from where impulses are transmitted along the afferent fibers of the trigeminal nerve to the sensory nuclei medulla oblongata, nuclei of the visual thalamus, from there to the cerebral cortex. From the brain stem and thalamus opticus, collaterals extend to the reticular formation. The motor nuclei of the medulla oblongata, red nucleus, substantia nigra, subcortical nuclei and cerebral cortex take part in the regulation of chewing. These structures are chewing center. Impulses from it travel through motor fibers (mandibular branch of the trigeminal nerve) to the masticatory muscles. In humans and most animals upper jaw motionless, therefore chewing is reduced to movements of the lower jaw, carried out in the following directions: from top to bottom, front to back and sideways. The muscles of the tongue and cheeks play an important role in holding food between chewing surfaces. Regulation of the movements of the lower jaw to carry out the act of chewing occurs with the participation of proprioceptors located in the thickness of the masticatory muscles. Thus, the rhythmic act of chewing occurs involuntarily: The ability to chew consciously and regulate this function at an involuntary level is presumably associated with the representation of the act of chewing in the structures of various levels of the brain.

When registering chewing (masticationography), the following phases are distinguished: rest, introducing food into the mouth, indicative, main, formation of a food bolus. Each of the phases and the entire period of chewing has a different duration and character, which depends on the properties and quantity of chewed food, age, appetite with which food is taken, individual characteristics, the usefulness of the masticatory apparatus and its control mechanisms.

Swallowing. According to Magendie's theory (Magendie, 1817), the act of swallowing is divided into three phases - oral free pharyngeal involuntary, fast and esophageal, also involuntary, but slow. From the crushed food mass moistened with saliva in the mouth, a food bolus is separated, which, with the movements of the tongue, moves towards the midline between the front part of the tongue and hard palate. At the same time, the jaws compress and the soft palate rises. Together with the contracted velopharyngeal muscles, it forms a septum that blocks the passage between the mouth and the nasal cavity. To move the bolus of food, the tongue moves backward, pressing on the palate. This movement moves the lump into the throat. At the same time, intraoral pressure increases and helps push the food bolus in the direction of least resistance, i.e. back. The entrance to the larynx is closed by the epiglottis. At the same time, compression of the vocal cords also closes the glottis. As soon as a lump of food enters the pharynx, the anterior arches of the soft palate contract and, together with the root of the tongue, prevent the lump from returning to the oral cavity. Thus, when the muscles of the pharynx contract, a bolus of food can only be pushed into the opening of the esophagus, which is expanded and moved towards the pharyngeal cavity.

Changes in pharyngeal pressure during swallowing also play an important role. The pharyngoesophageal sphincter is usually closed before swallowing. During swallowing, the pressure in the pharynx increases sharply (up to 45 mm Hg). When the high pressure wave reaches the sphincter, the sphincter muscles relax and the pressure in the sphincter quickly decreases to the level of external pressure. Thanks to this, the lump passes through the sphincter, after which the sphincter closes, and the pressure in it increases sharply, reaching 100 mm Hg. Art. At this time, the pressure in the upper part of the esophagus reaches only 30 mm Hg. Art. The significant difference in pressure prevents the bolus of food from refluxing from the esophagus into the pharynx. The entire swallowing cycle lasts approximately 1 second.

This entire complex and coordinated process is a reflex act, which is carried out by the activity of the swallowing center of the medulla oblongata. Since it is located close to the respiratory center, breathing stops every time the act of swallowing occurs. The movement of food through the pharynx and through the esophagus into the stomach occurs as a result of successively occurring reflexes. During the implementation of each link in the chain of the swallowing process, irritation of the receptors embedded in it occurs, which leads to a reflex inclusion of the next link in the act. Strict coordination components the act of swallowing is possible due to the presence of complex relationships various departments nervous system, starting from the medulla oblongata and ending with the cerebral cortex.

The swallowing reflex occurs when irritation of the sensory receptor endings of the trigeminal nerve, superior and inferior laryngeal and glossopharyngeal nerves embedded in the mucous membrane of the soft palate. Along their centripetal fibers, excitation is transmitted to the center of swallowing, from where impulses propagate along the centrifugal fibers of the upper and lower pharyngeal, recurrent and vagus nerve to the muscles involved in swallowing. The swallowing center operates on an “all or nothing” principle. The swallowing reflex occurs when afferent impulses reach the swallowing center in a uniform row.

A slightly different mechanism for swallowing liquids. When drinking by retracting the tongue without breaking the lingual-palatal bridge, negative pressure is formed in the oral cavity and the liquid fills the oral cavity. Then contraction of the muscles of the tongue, floor of the mouth and soft palate creates so high pressure that under its influence the liquid is, as it were, injected into the esophagus, which is relaxing at this moment, reaching the cardia almost without the participation of contraction of the pharyngeal constrictors and esophageal muscles. This process takes place within 2-3 seconds.

State educational institution

Higher professional education

Volgograd State Medical University

Department of Normal Anatomy

ABSTRACT

ON THE TOPIC

"Innervation of the salivary glands"

Volgograd, 2011

Introduction………………………………………………………………………. 3

Salivary glands…………………………………………………………… 5

Sympathetic innervation of the salivary glands…………………………….. ….7

Regulation of salivation…………………………………………… ………. ..9

Parasympathetic innervation of the salivary glands……………………….. …..11

Conclusion…………………………………………………… ………………. .12

List of references…………………………………………………………….13

Introduction

Salivary glands. There are three pairs of major salivary glands: parotid, submandibular and sublingual and minor salivary glands - buccal, labial, lingual, hard and soft palate. The large salivary glands are lobular formations that are easily palpable from the oral cavity.

Small salivary glands with a diameter of 1 - 5 mm are located in groups. The largest number of them is in the submucosa of the lips, hard and soft palate.

The parotid salivary glands (glandula parotidea) are the largest salivary glands. The excretory duct of each of them opens in the vestibule of the oral cavity and has valves and terminal siphons that regulate the excretion of saliva.

They secrete a serous secretion into the oral cavity. Its amount depends on the condition of the body, the type and smell of food, and the nature of irritation of oral receptors. The cells of the parotid gland also remove various drugs, toxins, etc. from the body.

It has now been established that the parotid salivary glands are endocrine glands (parotene affects mineral and protein metabolism). A histofunctional connection of the parotid glands with the genital, parathyroid, thyroid glands, pituitary gland, adrenal glands, etc. has been established. The parotid salivary glands are innervated by sensory, sympathetic and parasympathetic nerves. Passes through the parotid salivary gland facial nerve.

The submandibular salivary gland (glandula lubmandibularis) secretes a serous-mucosal secretion. The excretory duct opens on the sublingual papilla. Blood supply is provided by the mental and lingual arteries. The submandibular salivary glands are innervated by branches of the submandibular ganglion.

The sublingual salivary gland (glandula sublingualis) is mixed and secretes a serous-mucosal secretion. The excretory duct opens on the sublingual papilla.

Salivary glands

Parotid salivary gland (glandula parotis)

Afferent innervation of the gland is carried out by fibers of the auriculotemporal nerve. Efferent innervation is provided by parasympathetic and sympathetic fibers. Parasympathetic postganglionic fibers pass as part of the auriculotemporal nerve from the auricular ganglion. Sympathetic fibers pass to the gland from the plexus around the outer carotid artery and its branches.

Submandibular gland (glandula submandibularis)

Afferent innervation of the gland is carried out by fibers of the lingual nerve (from the mandibular nerve - the third branch of the trigeminal nerve, V pair cranial nerves). Efferent innervation is provided by parasympathetic and sympathetic fibers. Parasympathetic postganglionic fibers pass as part of the facial nerve (VII pair of cranial nerves) through the chorda tympani and the submandibular ganglion. Sympathetic fibers pass to the gland from the plexus around the external carotid artery.

Sublingual gland (glandula sublinguale)

Afferent innervation of the gland is carried out by fibers of the lingual nerve. Efferent innervation is provided by parasympathetic and sympathetic fibers. Parasympathetic postganglionic fibers pass as part of the facial nerve (VII pair) through the chorda tympani and the submandibular ganglion. Sympathetic fibers pass to the gland from the plexus around the external carotid artery. Efferent, or secretory, fibers of the large salivary glands come from two sources: parts of the parasympathetic and sympathetic nervous systems. Histologically, myelinated and unmyelinated nerves are found in the glands, following the course of the vessels and ducts. They form nerve endings in the walls of blood vessels, at the end sections and in the excretory ducts of the glands. Morphological differences between secretory and vascular nerves cannot always be determined. In experiments on the submandibular gland of animals, it was shown that the involvement of sympathetic efferent pathways in the reflex leads to the formation of viscous saliva containing a large amount of mucus. When the parasympathetic efferent pathways are irritated, a liquid protein secretion is formed. The closure and opening of the lumen of arteriovenular anastomoses and terminal veins is also determined by nerve impulses.

Sympathetic innervation of the salivary glands

The sympathetic innervation of the salivary glands is as follows: the neurons from which the preganglionic fibers arise are located in the lateral horns of the spinal cord at the level of ThII-ThVI. The fibers approach the superior ganglion, where they end in postganglionic neurons that give rise to axons. Together with the choroid plexus accompanying the internal carotid artery, the fibers reach the parotid salivary gland as part of the choroid plexus surrounding the external carotid artery, submandibular and sublingual salivary glands.

Irritation of the cranial nerves, in particular the chorda tympani, causes a significant secretion of liquid saliva. Irritation of the sympathetic nerves causes a slight separation thick saliva with a rich content of organic matter. Nerve fibers, when irritated, release water and salts, are called secretory, and nerve fibers, when irritated, release organic matter- trophic. With prolonged irritation of the sympathetic or parasympathetic nerve, saliva becomes depleted of organic substances.

If you first stimulate the sympathetic nerve, then subsequent stimulation of the parasympathetic nerve causes the release of saliva, rich in dense components. The same thing happens when both nerves are simultaneously irritated. Using these examples, one can be convinced of the relationship and interdependence that exists under normal physiological conditions between the sympathetic and parasympathetic nerves in the regulation of the secretory process of the salivary glands.

When the secretory nerves are transected in animals, a continuous, paralytic secretion of saliva is observed within a day, which lasts about five to six weeks. This phenomenon appears to be associated with changes in the peripheral ends of the nerves or in the glandular tissue itself. It is possible that paralytic secretion is due to the action of chemical irritants circulating in the blood. The question of the nature of paralytic secretion requires further experimental study.

Salivation, which occurs when nerves are irritated, is not a simple filtration of fluid from blood vessels through glands, but a complex physiological process resulting from the active activity of secretory cells and the central nervous system. Proof of this is the fact that irritation of the nerves causes salivation even after the vessels supplying blood to the salivary glands are completely ligated. In addition, in experiments with irritation of the chorda tympani, it was proven that the secretory pressure in the gland duct can be almost twice as high as the blood pressure in the vessels of the gland, but the secretion of saliva in these cases is abundant.

When the gland is working, the absorption of oxygen and the release of carbon dioxide by secretory cells sharply increases. The amount of water flowing through the gland during activity increases 3-4 times.

Microscopically, it was found that during the period of rest, significant amounts of secretion grains (granules) accumulate in the glandular cells, which during the operation of the gland dissolve and are released from the cell.

Regulation of salivation

Salivation is a reaction to irritation of receptors in the oral cavity, to irritation of receptors in the stomach, and during emotional arousal.

The efferent (centrifugal) nerves innervating each salivary gland are parasympathetic and sympathetic fibers. Parasympathetic innervation of the salivary glands is carried out by secretory fibers passing through the glossopharyngeal and facial nerves. Sympathetic innervation of the salivary glands is carried out by sympathetic nerve fibers, which begin from nerve cells lateral horns of the spinal cord (at the level of the 2nd-6th thoracic segments) and are interrupted in the superior cervical sympathetic ganglion.

Irritation of parasympathetic fibers leads to the formation of abundant and liquid saliva. Irritation of sympathetic fibers causes the release of a small amount of thick saliva.

The center of salivation is located in the reticular formation of the medulla oblongata. It is represented by the nuclei of the facial and glossopharyngeal nerves.

Sensitive (centripetal, afferent) nerves connecting the oral cavity with the center of salivation are the fibers of the trigeminal, facial, glossopharyngeal and vagus nerves. These nerves transmit impulses to the central nervous system from taste, tactile, temperature, and pain receptors in the oral cavity.

Salivation is carried out according to the principle of unconditional and conditioned reflexes. Unconditioned reflex salivation occurs when food enters the oral cavity. Salivation can also be a conditioned reflex. The sight and smell of food and sound stimulation associated with cooking lead to salivation. In humans and animals, conditioned reflex salivation is possible only in the presence of appetite.

Parasympathetic innervation of the salivary glands

Parasympathetic innervation comes from the superior and inferior salivary nuclei. From the superior nucleus, excitation is directed to the PYAS, PPS and the minor palatine salivary glands. Preganglionic fibers to the PPSG and PPSG go as part of the tympanic chord; they conduct impulses to the submandibular and sublingual vegetative nodes, where excitation switches to postganglionic secretory nerve fibers, which, as part of the lingual nerve, approach the PPSG and PPSG. Preganglionic fibers of the minor salivary glands go as part of the greater petrosal nerve to the pterygopalatine ganglion, from which postganglionic fibers as part of the greater and lesser palatine nerves approach the minor salivary glands of the hard palate.

From the inferior salivary nucleus, excitation is transmitted along preganglionic fibers that run as part of the inferior petrosal nerve to the auricular ganglion, from which postganglionic fibers as part of the auriculotemporal nerve innervate the ACSF.

The nuclei of the sympathetic division of the ANS are located in the lateral horns of the 2-6 thoracic segments of the spinal cord. Excitation from them enters the superior cervical sympathetic ganglion via preganglionic fibers, and then reaches the salivary glands via postganglionic fibers along the external carotid artery.

Conclusion

IN last years special attention is paid to the study of saliva, since it has been established important role saliva in maintaining oral homeostasis. Changes in the composition and properties of saliva affect the development of caries and periodontal pathology. Knowledge of the physiology of the salivary glands, the nature of salivation, as well as the composition and functions of saliva is necessary to understand the pathogenetic mechanisms of these diseases.

In recent years, new information has been obtained confirming the important role of saliva in maintaining homeostasis of the oral cavity. Thus, it has been established that the nature of salivation, quantitative and qualitative changes in saliva largely determine the resistance or susceptibility of teeth to caries. It is saliva that ensures the dynamic balance of tooth enamel and the constancy of its composition due to ion exchange.

List of used literature

1. Human anatomy R.P. Samusev Yu.M. Selin M.: Medicine 1995.
2. Great Medical Encyclopedia: In 36 volumes - M., 1958. - Volume 6.
3. Green N., Stout W., Taylor D. Biology: In 3 volumes - M., 2004. - Volume 3.
4. Human physiology / edited by M. Selin - M., 1994
5. Trevor Weston. Anatomical atlas 1998

Sympathetic nervous system

Its function is adaptive trophic (changes the level of metabolism in organs depending on the function they perform in certain environmental conditions).

It is divided into a central and peripheral section.

The central section is thoracolumbar, as it is located in the lateral horns of the spinal cord from the 8th cervical to the 3rd lumbar segment of the spinal cord.

These nuclei are called nucleus intermediolateralis.

Peripheral department.

This includes:

1) rami communicantes albi et grisei

2) nodes of 1st and 2nd order

3) plexuses

1) Nodes of the 1st order are ganglia trunci sympathici or nodes of the sympathetic trunks, which run from the base of the skull to the coccyx. These nodes are divided into groups: cervical, thoracic, lumbar and sacral.

Cervical - in these nodes there is a switching of nerve fibers for the organs of the head, neck and heart. There are 3 cervical nodes: ganglion cervicale superius, medium, inferius.

Thoracic - there are only 12 of them. Nerve fibers are switched in them to innervate the organs of the thoracic cavity.

Nodes of the 2nd order - are located in abdominal cavity in those places where unpaired visceral arteries depart from the aorta, these include 2 celiac nodes (ganglia celiaci), 1 superior mesenteric node (ganglion mesentericum superius),

1 inferior mesenteric (mesentericum inferius)

Both celiac and superior mesenteric nodes belong to the solar plexus and are needed for the innervation of the abdominal organs.

The inferior mesenteric node is needed to innervate the pelvic organs.

2) Rami communicantes albi - connect spinal nerves with the nodes of the sympathetic trunk and are part of the preganglionic fibers.

There are a total of 16 pairs of white connecting branches.

Rami communicantes grisei - connect nodes with nerves, they are part of postganglionic fibers, there are 31 pairs of them. They innervate the soma and belong to the somatic part of the sympathetic nervous system.

3) Plexuses - they are formed by postganglionic fibers around the arteries.

* Response plan for organ innervation

1. Center of innervation.

2. Preganglionic fibers.

3. The node in which the switching of nerve fibers occurs.

4. Postgangionary fibers

5. Effect on the organ.

Sympathetic innervation of the salivary glands

1. The center of innervation is located in the spinal cord in the lateral horns in the nucleus intermediolateralis of the first two thoracic segments.

2. Preganglinar fibers are part of the anterior root, spinal nerve and ramus communicans albus

3. Switching to ganglion cervicale superius.

4. Postganglionic fibers form the plexus caroticus externus

5. Decreased secretion.

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TO major salivary glands (glandulae salivariae majores) include paired parotid, sublingual and submandibular glands.

The large salivary glands belong to the parenchymal organs, which include:

parenchyma- a specialized (secretory) part of the gland, represented by the acinar section containing secretory cells where secretion is produced. The salivary glands include mucous cells that secrete a thick mucous secretion, and serous cells that secrete liquid, watery, so-called serous or protein saliva. The secretion produced in the glands is delivered through the system of excretory ducts to the surface of the mucous membrane in different departments oral cavity.

stroma- a complex of connective tissue structures that form the internal frame of the organ and contribute to the formation of lobules and lobes; in the layers of connective tissue there are vessels and nerves leading to the acinar cells.

Parotid gland

Parotid gland (glandula parotidea) is the largest of the salivary glands, which is located downward and anterior to auricle, at the posterior edge of the masticatory muscle. Here it is easily accessible for palpation.

Sometimes there may also be an accessory parotid gland (glandula parotidea accessoria), located on the surface of the masticatory muscle near the parotid duct. The parotid gland is a complex multilobulated alveolar gland consisting of serous cells that produce serous (protein) saliva. It distinguishes between the superficial part (pars superficialis) and the deep part (pars profunda).

The superficial part of the gland has a masticatory process and is located on the branch of the lower jaw and on the masticatory muscle. Sometimes there is also a superior process adjacent to the cartilaginous portion of the external auditory canal. The deep part often has pharyngeal and posterior processes. It is located in the mandibular fossa (fossa retromandibularis), where it is adjacent to the temporomandibular joint, mastoid process temporal bone and some neck muscles.

The parotid gland is covered by the parotid fascia, which forms the capsule of the gland. The capsule consists of superficial and deep layers covering the gland from the outside and inside. It is closely connected to the gland by connective tissue bridges that continue into septa that separate the lobules of the gland from each other. The deep layer of the capsule in the area of ​​the pharyngeal process is sometimes absent, which creates conditions for the purulent process to spread into the peripharyngeal space during parotitis.

Parotid duct(ductus parotideus), or Stenon's duct The name "Stenon's duct" is derived from the name of the anatomist who described it. Such anatomical terms are called eponyms. Eponyms are often used in clinical practice along with nomenclature anatomical terms., is formed by the fusion of interlobar ducts and reaches a diameter of 2 mm. Leaving the gland at its anterior edge, it lies on masticatory muscle 1 cm below the zygomatic arch, pierces the buccal muscle and opens on the mucous membrane of the cheek into the vestibule of the mouth at the level of the 1st-2nd upper molars. The accessory parotid gland is usually located above the parotid duct, into which its own duct flows.

Passes through the thickness of the parotid gland external carotid artery And submandibular vein. Inside the gland, the external carotid artery divides into two terminal branches - maxillary And superficial temporal artery.

Also passes through the parotid gland facial nerve. In it, it is divided into a number of branches radiating from the area of ​​the earlobe to facial muscles faces.

Blood supply parotid salivary gland is carried out by branches external carotid artery(a. carotis externa), among which posterior auricular artery(a. auricularis posterior), passing obliquely backwards over top edge posterior belly of the digastric muscle, transverse artery of the face(a. transversa faciei) and zygomaticoorbital artery(a. zygomaticoorbitalis), extending from superficial temporal artery (a. temporalis superficialis), as well as deep auricular artery(a. auricularis profunda), extending from maxillary artery(a. maxillaris) (see Fig. 10). The excretory duct of the parotid gland is supplied with blood from the transverse artery of the face. The arteries of the parotid gland have numerous anastomoses with each other and with the arteries of nearby organs and tissues.

Venous drainage provided by the veins accompanying the excretory ducts of the gland. Merging, they form parotid veins Ezes (vv. parotideae), carrying blood into mandibular(v. retromandibularis) and facial veins(v. facialis) and further into internal jugular vein(v. jugularis interna).

On the way to the mandibular vein, blood from the upper part of the gland also flows into transverse vein of the face(v. transversa faciei), from its middle and lower part - in masticatory veins(vv. maxillares) and pterygoid plexus(plexus pterygoideus), from the anterior part of the gland - in anterior auricular veins(vv. auriculares anteriores). From the postauricular part of the gland, venous blood flows into posterior auricular vein(v. auricularis posterior), sometimes - in occipital veins(vv. occipitales) and further to external jugular vein(v. jugularis externa).

Lymphatic drainage carried out mainly in deep parotid nodes(nodi parotidei profundi), which includes preauricular, inferior auricular and intraglandular nodes,

and also in superficial parotid nodes(nodi parotidei superficiales). Of these, lymph is directed to superficial And lateral deep cervical ganglia.

Innervation parotid gland is carried out by the parotid branches auriculotemporal nerve(n. auriculotemporalis), extending from mandibular nerve(n. mandibularis - III branch of n. trigeminus). The parotid branches (rr. parotidei) include the sensory ones, the following in the composition trigeminal nerve, and autonomic nerve fibers.

The autonomic innervation of the parotid gland is carried out by parasympathetic postganglionic nerve fibers arising from ear node(ganglion oticum), located on the medial surface of the mandibular nerve under the foramen ovale, and sympathetic postganglionic nerve fibers extending from upper cervical node(ganglion cervicale superius).

Preganglionic parasympathetic nerve fibers originate from inferior salivary nucleus(nucl. salivatorius inf.), located in the medulla oblongata; then in the composition glossopharyngeal nerve(n. glossopharyngeus - IX pair of cranial nerves) and its branches (n. tympanicus, n. petrosus minor) reach ear node(ganglion oticum). From the ear ganglion, postganglionic nerve fibers follow branches in the parotid gland auriculotemporal nerve.

Parasympathetic nerve fibers stimulate the secretion of the gland and expand it blood vessels.

Preganglionic sympathetic nerve fibers begin from the autonomic nuclei of the upper thoracic segments of the spinal cord and, as part of the sympathetic trunk, reach the superior cervical ganglion.

Sympathetic postganglionic nerve fibers come from the superior cervical ganglion and approach the parotid gland as part of plexus of external carotid artery(plexus caroticus externus) along the branches of the external carotid artery supplying blood to the gland. Sympathetic innervation has a constricting effect on blood vessels and inhibits the secretion of the gland.

Innervation of the lacrimal and salivary glands

The afferent pathway for the lacrimal gland is n. lacrimalis (branch of n. ophthalmicus from n. trigemini), for the submandibular and sublingual - n. lingualis (branch of n. mandibularis from n. trigemini) and chorda tympani (branch of n. intermedius), for the parotid - n. auriculotemporal and n. glossopharyngeus.

Efferent parasympathetic innervation of the lacrimal gland. The center lies in the upper part of the medulla oblongata and is connected with the nucleus of the intermediate nerve (nucleus salivatorius superior). Preganglionic fibers are part of n. intermedius, then n. petrosus major to ganglion pterygopalatinum. This is where the postganglionic fibers begin, which are part of n. maxillaris and further its branches, n. zygoma ticus, through connections with n. lacrimalis reach the lacrimal gland.

Efferent parasympathetic innervation of the submandibular and sublingual glands. Preganglionic fibers come from the nucleus salivatorius superior as part of n. intermedius, then chorda tympani and n. lingualis to the ganglion submandibulare, from where the spinal glionic fibers that reach the glands begin.

Efferent parasympathetic innervation of the parotid gland. Preganglionic fibers come from the nucleus salivatorius inferior as part of n. glossopharyngeus, then n. tympanicus, n. petrosus minor to ganglion oticum. This is where the postganglionic fibers begin, going to the gland as part of n. auriculotemporalis. Function: increased secretion of the lacrimal and named salivary glands; dilation of gland vessels.

Efferent sympathetic innervation of all these glands. Preganglionic fibers begin in the lateral horns of the upper thoracic segments of the spinal cord and end in the superior cervical ganglion of the sympathetic trunk. Postganglionic fibers begin in the named node and reach the lacrimal gland as part of the plexus caroticus internus, to the parotid gland as part of the plexus caroticus externus, and to the submandibular and sublingual glands through the plexus caroticus externus and then through the plexus facialis.

There is nothing anywhere about the minor salivary glands, but! they are located in the oral mucosa, which is innervated by the branches of the inferior alveolar nerve ( n. alveolaris inferior) (- mandibular nerve - trigeminal nerve), and since the mucous membrane is innervated trigeminal nerve, like all other glands, then further information will flow similarly to other structures.

Ticket 48.

1. Osteofibrous canals (flexor and extensor retinaculum, carpal canals), sheaths (synovial) of muscle tendons upper limb. Synovial bursae. EXTENSORS

Subcutaneous fatty tissue the posterior region of the wrist is loose, moderately developed. Edema fluid easily accumulates in it. The proper fascia of the dorsal surface of the wrist is thickened and forms the extensor retinaculum, retinaculum musculorum extensoram. Under it there are 6 bone-fibrous canals formed as a result of the departure from the retinaculum mm. extensoram fascial septa attached to the bones and ligaments of the wrist. The canals contain the tendons of the extensor muscles of the wrist and fingers, surrounded by synovial sheaths.

Starting from the medial (ulnar) side, these are the following channels: 1. Canal of the extensor carpi ulnaris, m. extensor carpi ulnaris. Its synovial sheath extends from the head of the ulna to the insertion of the tendon at the base of the fifth metacarpal bone. 2. Canal of the extensor of the little finger, m. extensor digiti minimi. The synovial sheath of the extensor of the little finger is located proximally at the level of the distal radioulnar joint, and distally - below the middle of the fifth metacarpal bone. 3. Tendon channel m. extensor digitorum and m. extensor indicis, enclosed in a triangular synovial vagina with the base facing the fingers 4. Canal m. extensor pollicis longus. The tendon of this muscle, located in its own synovial vagina, vagina tendinis m. extensoris pollicis longi, turns at an acute angle to the lateral side and crosses the radial extensor tendons of the hand in front, mm. extensores carpi radiales longus et brevis. 5. Osteofibrous canal of the radial extensors of the hand, mm. extensores carpi longus et brevis, is located lateral and deeper than the previous one. The synovial sheaths of the tendons of these muscles can communicate with the cavity of the wrist joint. 6. Channel m. abductor pollicis longus and m. extensor pollicis brevis is located on the lateral surface of the styloid process of the radius.

FLEXORS Synovial sheaths on the palmar surface contain: the first - the tendons of the superficial and deep flexor of the fingers, the second - the long flexor of the first finger. Both synovial sheaths are located in the carpal tunnel (canalis carpalis), which is limited by the bones of the wrist and the retinaculum flexorum. At the top, the synovial sheaths extend 1-1.5 cm above the retinaculum flexorum. Below, the first sheath forms an expansion in the area of ​​the tendons of the II, III, IV fingers, ending in the middle of the metacarpal bones. The synovial sheath surrounding the flexor tendon of the fifth finger starts from the level of the wrist joint and reaches distal phalanx V finger. The II, III and IV fingers have independent synovial sheaths for the tendons of the superficial and deep flexor of the fingers. The second synovial sheath for the tendon of the long flexor of the first finger extends to the distal phalanx. Synovial bursa (lat. bursa synovialis) - a small flattened cavity lined synovial membrane, delimited from surrounding tissues by a capsule and filled with synovial fluid. By location, subcutaneous, subfascial, subtendinous and axillary synovial bursae are distinguished.1 Synovial bursae of the upper limb, bursae membri superioris.2Trapezius muscle subtendinous bursa, b. subtendinea m.trapezii. Localized between the ascending part of m. trapezius and the spine of the scapula. 3 Acromial subcutaneous bursa, b. subcutanea acromialis 4Subacromial bursa, b. subacromialis. Located under the acromion and deltoid muscle on the capsule shoulder joint. 5 Subdeltoid bursa, b. subdeltoidea. Located between the deltoid muscle and the capsule of the shoulder joint. Sometimes connected to the subacromial bursa 6Bursa of the coracobrachialis muscle, b. m.coracobrachialis. It is localized below the apex of the coracoid process between the tendons of the subscapularis and coracobrachialis muscles. 7 Subtendinous bursa of the infraspinatus muscle, b. subtendinea m. infraspinati. Located between the infraspinatus tendon and the capsule of the shoulder joint. 8 Subtendinous bursa of the subscapularis muscle, b. subtendinea m. subscapularis. Located between the tendon of the subscapularis muscle and the capsule of the shoulder joint. Connects to the articular cavity. 9Tendinous bursa of the teres major muscle, b. subtendinea m. teretis majoris. Located between the tendon of the corresponding muscle and the humerus. 10The subtendinous bursa of the latissimus dorsi muscle, b. subtendinea m. latissimi dorsi. Located between the tendons of the teres major muscle and the latissimus dorsi muscle11 Ulnar subcutaneous bursa, b.subcutanea olecrani. Located between the olecranon and the skin. 12 Ulnar intratendinous bursa, b.intratendinea olecrani. Located inside the triceps brachii tendon, near the olecranon process. 13 Subtendinous bursa of the triceps brachii muscle, b. subtendinea m. tricipitis brachii. It is located between the tendon of the muscle of the same name and the olecranon process. 14Biceps-radial bursa, b. bicipitoradialis. Localized between the biceps tendon and the radial tuberosity. 15 Interosseous ulnar bursa, b.cubitalis interossea. Located between the biceps tendon and ulna or oblique chord.