Famine: location, structure and functions. Fine intestine folds of the small intestine consist of

text_fields.

text_fields.

arrow_upward

Small intestine (Intestinum Tenue) - The body in which the transformation of food substances in soluble compounds continues. Under the action of the enzymes of the intestinal juice, as well as the pancreas and bile juice, proteins, fats and carbohydrates are cleaved respectively to amino acids, fatty acids and monosaccharides.

These substances, as well as salts and water absorbed into the blood and lymphatic vessels and are spread to organs and tissues. The intestine performs a mechanical function, pushing the chimus in the caudal direction. In addition, in the small intestine, specialized neuroendocrine (enteroendocrine) cells form some hormones (serotonin, histamine, gastrin, cholecystokinin, secretine and others).

The subtle intestine represents the longest part of the digestive tube (in a living person - up to 5 m, on the corpse - 6-7 m). It starts from the gastric gatekeeper and ends with the iliac-slurry (ileocecular) hole at the place of the transition of the small intestine in thick. The delicate intestine is divided into duodenal, skinny and iliac. The first short - 25-30 cm; Approximately 2/5 of the length of the rest of the subtle intestines falls on a skinny, and 3/5 - on the ileum. The width of the intestine gradually decreases from 4-6 cm in duodenum to 2.5 cm in the iliac.

Fountain bowel wall structure

text_fields.

text_fields.

arrow_upward

The structure of the wall of the small intestine is similar in all departments. It consists of a mucous membrane, a submoticon base, muscular and serous shells.

Mucous membrane

The mucous membrane has a typical relief due to macro and microscopic formations, characteristic of only thin intestines. These are circular folds (more than 600), patches and crypts.

Spiral or circular foldsthere are no more than 1 cc gloss than 1 cm. The length of such folds from half to two thirds, sometimes to the whole circumference of the intestine walls. When filling the intestine, the folds are not smoothed. When moving to the distal end of the intestine, the size of the folds decreases, and the distance between them increases. The folds are formed by the mucous membrane and the submembrance base (see atl.).

Fig. 4.15. Intestinal Pumps and Crypts Fine Incons

Fig. 4.15. Intestinal patches and crypts of the small intestine:
A - scanning microscopy;
B and B - light microscopy:
1 - Vile in the longitudinal section;
2 - Crypts;
3 - glassworm cells;
4 - Patenet cells

The whole surface of the mucosa in the folds is covered between them intestinal Villains(Fig. 4.15; see atl.). The total number exceeds 4 million. These are miniature sheets or finger-shaped mucous membranes, reaching in a thickness of 0.1 mm, and height from 0.2 mm (in duodenalistician) up to 1.5 mm (in the iliac). The amount of villi is also different: from 20-40 per 1 mm 2 in the duodenum to 18-30 per 1 mm 2 - in the iliac.

Forms every navy mucous membrane; Muscular plate mucosa and submucoscent in it do not penetrate. The surface of the villi is covered with single-layer cylindrical epithelium. It consists of suction cells (enterocytes) - about 90% of the cells, between which the glasswall cells separating the mucus, and enteroendocrine cells (about 0.5% of all cells) are enclosed. The electron microscope made it possible to find that the surface of enterocytes is covered with numerous microvills forming the brush cut. The presence of microwave increases the suction surface of the mucous membrane of the small intestine to 500 m 2. The surface of the microwave is covered with a layer of glycocalca, in which there is a hydrolytic enzymes that split carbohydrates, polypeptides and nucleic acids. These enzymes provide the process of clutch digestion. Split substances are transported through the membrane inside the cell - their suction occurs. After intracellular transformations, the sedentary substances are released into the connecting tissue and penetrate the blood and lymphatic vessels. The side surfaces of the epithelium cells are firmly interconnected using intercellular contacts, which prevents substances from entering the intestinal lumen to sub-epipitel connective tissue. The number of scattered single-shaped cells is gradually increasing from the duodenum to the ileum. The mucus allocated by them wets the surface of the epithelium and contributes to the promotion of food particles.

The base of the Village consists of loose connective tissue Own layer of mucous membrane with mesh elastic fibers, blood vessels and nerves are branched in it. In the center of Vorki, it takes a blindly ending in the top of the lymphatic capillary, communicating with the plexus of the lymphatic capillaries of the submembratus layer. Along the vice, smooth muscle cells are laid connected by reticular fibers with a basal epithelium membrane and a stroma villus. During digestion, these cells are reduced, the veins are shortened, thicken, and the contents of their blood and lymphatic vessels are extruded and goes into the total blood flow and lymph. With the relaxation of the muscular elements, the Village is spreads, swelling, and the nutrients that are used through the cut epithelium come to the vessels. The most intense suction in the duodenum and the cushions.

Between the Villages there are tubular foaming of the mucous membrane - cryptor intestinal glands (Fig. 4.15; atl). Crypt walls are formed by secretory cells of various species.

Based on each crypt, there are package cells containing large secretory granules. They contain a set of enzymes and lysozyme (bactericidal) between these cells there are minor unoccalued cells, due to the division of which the crypt and villium epithelium is updated. As it was established, the renewal of the intestinal epithelial cells in humans occurs every 5-6 days. Above the cells of the package are cells released mucus, and enteroendocrine cells.

In total in the small intestine more than 150 million crypt - up to 10 thousand per 1 cm 2.

In the sublifting layer of the duodenum there are branched tubular duodenal glands, separating the mucous secret into intestinal crypts, involved in the neutralization of hydrochloric acid coming from the stomach. Some enzymes (peptidases, amylase) are also detected in the secret of these glands. The greatest amount of glands in the proximal sections of the intestine, then it gradually decreases, and in the distal department they disappear at all.

In its own plate of mucous membrane, many reticular fibers forming the "core" of the Village. The muscular plate consists of the inner circular and the outer longitudinal layers of smooth-muscular cells. From the inner layer, individual cells are deployed into the tubing fabric of the veil and into the subliminate base. In the central part of the Village lies blindly closed lymphatic capillary, often referred to as the Milky Vasca, and the network of blood capillaries. Similarly, the nerve fibers of the Mason's plexus are located.
Throughout the small intestine, the lymphoid fabric forms small solitary follicles in the mucous membrane, a value of up to 1 - 3 mm in the diameter. In addition, in the distal departure of the ileum on the side, the opposite to attachment of the mesenter, groups of nodules, forming follicular plaques (peeper plaques) are located (Fig. 4.16; atl).

Fig. 4.16. The structure of the subtle intestine

Fig. 4.16. The structure of the small intestine:
1 - muscular shell;
2 - mesentery;
3 - serous shell;
4 - single follicles;
5 - circular folds;
6 - mucous membrane;
7 - Follicular Plaska

These are flat, elongated along the intestine of the plates reaching several centimeters in length and 1 cm in width. Follicles and plaques, as in general, lymphoid fabric, perform a protective role. Children from 3 to 15 years have about 15,000 single lymphatic nodules. In old age, their number decreases. The number of plaques also decreases with age from 100 in children up to 30-40 in adults, old people have almost no found. In the area of \u200b\u200bplaques, intestinal villi are usually absent.

Sublifting shell

Fat cells are often found in the submucosal basis. Here are the vascular and nervous plexus, and in the duodenum is a secretory departments of the glands.

Muscular shell

The muscular sheath of the small intestine is formed by two layers of muscle tissue: internal, more powerful, circular and outdoor - longitudinal. Between these layers, there is an intertwine nervous plexus, which regulates the abbreviations of the intestinal wall.

The motor activity of the small intestine is represented by peristaltic, wave-like movements, and rhythmic segmentation (Fig. 4.17).

Fig. 4.17. Motoric of the small intestine:
A - pendulum movement (rhythmic segmentation); B - peristaltic movements

They arise due to the reduction of circular muscles, spread in the intestine from the stomach to the anal hole and lead to the promotion and mixing of the chimus. Sections of reduction alternate with areas of relaxation. The frequency of abbreviations is reduced towards the upper intestinal departments (12 / min) to the lower (8 / min). These movements are regulated by the vegetative nervous system and hormones, most of which are formed in the gastrointestinal tract. Sympathetic nervous system Inhibits the motor activity of the small intestine, and parasympathetic enhances it. The intestinal movements are preserved after the destruction of the wandering and sympathetic nerves, but the strength of abbreviations is reduced, which indicates the dependence of these innervation cuts; This is true for the peristalsis. Segmentation is associated with the smooth muscles of the intestines that can react to local mechanical and chemical incentives. One of those chemical substances It is serotonin, which is formed in the intestines and stimulates his movement. Thus, the reductions of the small intestine are regulated by external nervous bonds, the activity of the most smooth muscle and local chemical and mechanical factors.

In the absence of food intake, peristaltic movements prevail contributing to the promotion of chimus. Meal inhibits them - begin to prevail the movements associated with mixing the contents of the intestine. Duration and intensity of motility depends on the composition and caloric content of food and decreases in a row: fats - proteins - carbohydrates.

Serous shell

Serous shell covers the delicate intestine from all sides, with the exception of a duodenum, which is covered with peritoneum only in front.

Duodenum

text_fields.

text_fields.

arrow_upward

Duodenum (Duodenum)it has a horseshoe form (see atl.). The initial segment of the intestine is covered with trousers from three sides, i.e. Located intraperitoneally. The remaining majority is incremented to the rear. abdominal wall And the peritoneal is covered in front. The remaining walls of the guts have a connective tissue (advential) shell.

The intestine is distinguished by the upper part starting from the gastroincing of the stomach and lying at the level I of the lumbar vertebra, which descends on the right along the spine to the level III of the lumbar vertebrae, and the bottom, passing after a small bending, at the level of the II lumbar vertebra, to the ... The upper part lies under the liver, ahead of the lumbar part of the diaphragm, descending adjacent to the right kidney, is behind the gallbladder and the transverse colon, and bottom part Lies near the aorta and the lower hollow vein, in front of it crosses the root of the mesentery of the hen intestine.

In the bend of the duodenum there is a pancreatic head. The output dump of the latter, together with the overall bile duct, permeates the wall of the descending part of the intestine and opens on the elevation of the mucous membrane, which is called a large papilla. Very often, 2 cm above the large papilla is made by small, which offers an extension of the pancreas.

The duodenum bundles are connected to the liver, kidneys and a transverse colon. In the hepatic and duodenal ligament pass overall bile duct, Mortal vein, hepatic artery and lymphatic liver vessels. In the rest of the bundles are arteries, blood supplying stomachs and mesenters.

Skinny and iliac

text_fields.

text_fields.

arrow_upward

Skinny (Jejunum) and iliac (ileum) intestine (see atl.) Covered from all sides by a serous shell (peritoneum) and movably suspended to the rear wall of the belly on the mesentery. They form a lot of loops, which in a living person, thanks to peristaltic contractions, constantly change their shape and position by filling most Puritini cavities.

The anatomical border between the skinny and iliacs does not exist; The loops first lie mainly in the left side of the abdomen, and the loops of the second occupy its middle and the right part. A large gland arrives in front to the small intestine. In the right bottom of the abdomen (in the iliac pit), the ileum opens into the primary part of the thick. Blood vessels and nerves are suitable for mesenter to the intestines.

Power supply of the small intestine

text_fields.

text_fields.

arrow_upward

The blood supply to the small intestine is carried out through the mesenteric arteries and the hepatic artery (duodenum). The delicate intestine is innervated from the plexus of the autonomic nervous system of the abdominal cavity and the wandering nerve.

The mucous membrane of the small intestine according to the functionality and uniqueness of the structure resembles the engine compartment of the Range Rover's expensive SUV, in which the car designers have built the maximum number of mechanisms and units into a limited volume of the increasing space, ensuring reliability and durability of the automotive brand.

Maximum protection and healthy state of mucosa is necessary for the well-coordinated work, one of which is one of the components of which is. Partial damage to epishet cells is not dangerous for the body. With a mass damage, fast recovery is impossible. The regeneration disorder reduces the suction and protective functions of intestinal veins.

In the conditions of daily flow of various information, basic knowledge of the appointment, structure of the mucous small intestine, the symptoms and diseases, methods and methods of treatment, the prevention given in the article will be useful to every concerned person.

The main task of the intestinal mucosa is the next stage of the splitting of nutrients enzymes of intestinal juice with further proceeding products in the blood, followed by transport in the cells of the body.

Additionally, the mucous membranes protect the recycled nutritional mass from the penetration of toxins, microorganisms. A feature of the structure of the body created by nature is a small total area of \u200b\u200b0.58-0.72 m², which increases during operation of five to seven times, to 5.5 m².

During reception of food, the movement of the Village ensures maximum absorption of the nutrient mixture. Chemical, mechanical stimuli also lead to the movement of villi, providing antimicrobial, counter-toxic protection of the body.

Different causes lead to a deterioration in the operation of the mucosa of the small intestine. What should pay attention to first?

General symptoms of the disease

Depending on the severity, signs of illness are manifested in the form:

• Pain attacks in the abdomen manifesting periodic battles.
• Liquid stools 2-3 times a day.
• Stable alternation of diarrhea and constipation.
• A painful reaction to the manual examination of the small intestine.
• Sensations of transfusion of fluid in the intestine when the position of the body is changed.
• Reduced body weight.

Important! Due to the similarity of the symptoms of the GTS Disease, the hepatologist is determined.

The listed symptoms indicate the appearance inflammatory processes In the mucous small intestine, the emergence of one of the types of gastrointestinal disease.

Diagnosis of the disease

To clarify the location of the mucous membrane, the source of inflammation and confirmation of the diagnosis uses survey methods:

Forms of the disease, causes of occurrence

Occurring disease processes are called inflammatory disease mucous membrane of the small intestine. Depending on the causes and speed of the flow, enteritis is divided into acute and chronic forms.

Acute enteritis

Causes of occurrence

• Poisoning of the body with food toxicological infection.
• Abuse of strong alcohol, sharp, coarse food.
• Bacterial, viral infection.
• Allergies to products.

Starting with diarrhea, vomiting, nausea, spastic pains, the disease passes to the next stage, leading to the rise of temperature to 40 ° C and higher, sharp decrease in vascular tone, intoxication, weakening the body.

Treatment

Features acute form Enititis requires a mandatory premises of the patient to the hospital under observation and treatment with a gastroenterologist.

An integrated treatment approach determines its effectiveness. Receiving assigned medicines improves, ensures the development of the necessary enzymes, relieves the symptoms of dehydration, restore the balance of fluid in the body. The use of sorbents accelerates the withdrawal of toxic substances from the body, leads to normal the defecation process. Immunostimulators, vitamins contribute to the rapid restoration of the body.

The effect of treatment will be not complete without the use of a special diet aimed at. The patient consumes foods and dishes with a puree, soft consistency to eliminate injuries of the organ during the healing period.

Shown to use:

• Vegetarian soups, faint chicken broth.
• Fish, meat in boiled, vapor cooking.
• Boiled, vapor rice, potatoes, steady vegetables.
• Compote, Kissel.
• Low-fat dairy products.

It is forbidden to use:

• Salads from vegetables and fruits with coarse fiber.
• Smoked, fried dishes.
• Mushrooms regardless of the method of preparation.
• Alcohol, kvass, soda.
• Spices, sharp seasonings.
• Fast carbohydrates in the form of flour sweets.

To facilitate digestion, it is necessary to eat small portions 5-6 times a day.

Important! In the period of exacerbation, the first 3-4 days must be fully refrained from food. The beginning of reception of food is agreed with the gastroenterologist.

When infection with the mucous small intestine, streptococci and aggressive microflora develops primary stage chronic disease. Related chronic diseases internal organs A person provoke a 15-20% of patients to the emergence of secondary chronic enteritis.

The painful sensations from the manual examination of the abdomen, the sense of fluid movement in the intestines, flatulence, the decline in body weight is important symptoms of enteritis, which switched to the protracted stage.

Treatment

As a result of the chronic form of inflammation of the mucous membrane, the absorption of nutrients deteriorates, digestion of food is disturbed.

Changes in the course of long-term change in the structure of the mucosa prevent the rapid regeneration of the organ.

In the treatment of chronic form, the combination of medicinal nutrition with medication therapy is used. Courses are appointed by the reception of drugs with enveloping, knitting properties. An intravenous nutrition is used, accepted. In some cases, hormonal, antibacterial substances are prescribed, vitamin complexes for the recovery of metabolism.

During the unloading of the digestive system, adherence to a special diet, which is used for a long time, sometimes transition to a lifetime formation. The food should have an enveloping effect, do not irritate the stomach. For feeding, a reusable method is used, 5-7 times a day. When gaining pain, it is necessary to use oatmeal, kissel, refusing hard food.

After improving the condition, the patient of 1.5-2 months is obliged to observe a diet, eliminating strong heating and cooling of products, rigid food with the presence of fiber. In eating, 40-70% decreases the amount of carbohydrates, fats, salt content (up to 6 g / day). At the same time, the norm of protein for an adult is preserved.

• Swivel vegetable soups.
• Lenten fish, meat in boiled or vapor cooking.
• Steam omelet of eggs, egg skey.
• Well ruled cereals (oatmeal, buckwheat, white rice).
• Boiled vegetables, fruits.
• Lean milk products.
• Surround white bread.

• Extractable broths.
• Alcohol, smoking.
• Chilled, carbonated drinks, juices.
• Fresh vegetables, fruit.
• Milk.

Important! Prolonged improvements occurs only in the case of continuous unloading of the gastrointestinal tract and restoration of the ability to regenerate the mucous membrane of the small intestine.

Help by complex treatment The mucous membrane of the small intestine is the use of medicinal plants known to a wide circle of people.

Recipes of traditional medicine

Widely well-known medicinal plants are used in addition to the main program of recovery to remove inflammation, eliminate spasm, combating microbes, enveloping organ and relieve pain:

• An infusion of chamomile, calendula, is more often used from herbal infusions.

The use of infusions eliminates the body from toxins, diarrhea, pain in the intestine.

• In chronic enterocolitis, it helps the use of dirty apples cooked on the water bath decoction blackberries, cherry fruits.

• Additional reception of freshly squeezed drugs of medicinal plants in a mixture with an equal volume of honey improves the effect of the course of drug therapy.

Important! Quality, dosage, frequency of use of recipes folk Medicine Installs the attending hepatologist.

Prevention

The main thing to exclude the disease of the mucous small intestine is the observance of the rational power mode. The food diet should be balanced by the number of proteins, carbohydrates of fats, trace elements, vitamins.

It is allowed only by quality products, the gifts of nature of famous origin. In this case, food itself provides a preventive and therapeutic effect.

With the appearance of symptoms and pain, it is necessary to subscribe to specialists to identify and timely treat the metabolic disorder, endocrine diseases, disease gasts. Compliance with the rules of personal hygiene, prescription reception of drugs only to the appointment of doctors must be respected by every person.

An important link to strengthen vascular system and accelerating the treatment of inflammation of the mucous membrane is a combination of useful natural factors - sea climate, drinking mineral waters, use of mud, healthy climate - with dosage exercisecapable of extending vital activity and longevity.

Anton Palaznikov

Gastroenterologist, therapist

Work experience more than 7 years.

Professional skills: Diagnosis and treatment of diseases of the tract and biliary system.

Gastrointestinal tract of a person is fine system Interpretations and interaction of digestive organs. All of them are inextricably linked with each other. Violations of one body can lead to a failure of the entire system. All of them perform their tasks and ensure the normal functioning of the body. One of the gastrointestinal bodies is a small intestine, which together with thick forms the intestine.

Small intestine

Located an organ between the colon and the stomach. Consists of three departments overgoing each other: duodenal, skinny and iliac guts. In the small intestine, the food porridge treated with gastric juice and saliva is exposed to the pancreas, intestinal juice and bile. With stirring in the enlightenment of the Himus organ, the products of its splitting are finally digested and absorbed. There is a small intestine in the middle area of \u200b\u200bthe abdomen, its length is about 6 meters in an adult.

In women, the gut is a little shorter than men. Medical studies have shown that a dead person has a longer organ than a living, which is due to the lack of muscle tone at the first. Skinny and iliac small intestine are called the mesenteric part.

Structure

The subtle intestine of a pipe-shaped shape with a length of 2-4.5 m. At the bottom, it borders with a blind intestine (its ileocecular valve), in the top - with the stomach. The duodenum is located in the back of the abdominal cavity, has a s-shaped. In the center of the peritoneum is a skinny intestine, the loops of which are covered with a shell on all sides and are free. In the lower part of the peritoneum there is a iliac, which is characterized by an increased amount of blood vessels, their large diameter, thick walls.

The structure of the small intestine allows nutrients Quickly absorb. This is due to microscopic growing and vile.

Departments: duodenum

The length of this part is about 20 cm. The intestine seems to envelop the loop in the form of the letter C, or horseshoes, the head of the pancreas. The first part of it is ascending - in the gatekeeper of the stomach. The descending length does not exceed 9 cm. Near this part there are a common gallstone and a liver with a petrose vein. The bottom bending of the intestine is formed at the level of the 3rd lumbar vertebra. Next door are the right kidney, a common bull duct and liver. The furrow of the total bile duct goes in the gap between the descending part and the head of the pancreas.

The horizontal department is located in the horizontal position at the level of the 3rd lumbar vertebra. The upper part turns into a skinny, making a sharp bend. Almost the entire duodenal intestine (except ampoule) is located in the retroperitoneal space.

Departments: Skinny and iliac

The following departments of the small intestine - skinny and iliacs are considered together due to their similar structure. This is a constituent mesenteric component. Seven hinges are lying in the abdominal cavity (left top part). The front surface is bordered by the gland, behind - with parietal peritoneum.

In the lower right of the peritoneum is the iliac, the last loops of which are adjacent to the bladder, the uterus, the rectum and reach the cavity of the small pelvis. In different parts, the diameter of the small intestine ranges from 3 to 5 cm.

Functions of the small intestine: endocrine and secretory

The small intestine in the human body performs the following functions: endocrine, digestive, secretory, suction, motor.

Per endocrine function Special cells correspond to peptide hormones synthesize. In addition to ensuring the regulation of intestinal activities, they also affect other organism systems. In the duodenum, these cells are concentrated in the greatest quantity.

The active work of the glaired sheath gland gland ensures the secretory functions of the small intestine due to the selection of intestinal juice. Approximately 1.5-2 liters are secreted by an adult per day. Intestinal juice contains disaccharisade, alkaline phosphatase, lipase, cathepsins that participate in the process of decomposition of food kil to fatty acids, monosaccharides and amino acids. A large amount of mucus contained in juice protects the delicious intestine from aggressive influences and chemical irritations. Also, the mucus takes part in the absorption of enzymes.

Suction, motor and digestive functions

The mucous membrane has the ability to suck food splitting foods, medication drugs and other substances that strengthen immunological protection and secretion of hormones. The small intestine in the suction process supplies water, salts, vitamins and organic compounds through lymphatic and blood capillaries in the most remote organs.

Longitudinal and internal (ring) muscles of the small intestine create conditions for moving along the organ of food kil and its mixing with gastric juice. The rubbing and digestion of the edible lump is provided by its separation into small parts during the movement process. The small intestine takes an active part in food digestion processes exposed to enzyme splitting under the influence of intestinal juice. Food absorption in all intestinal deposits leads to the fact that only non-represented and non-redeemed foods fall into the colon along with tendons, fascia and cartilage cloth. All functions of the small intestine are inextricably linked together and together provide normal productive operation of the organ.

Diseases of the subtle intestine

Violations of the body lead to dysfunction of the entire digestive system. All parts of the small intestine are interconnected, and pathological processes in one of the departments cannot but affect the rest. The clinical picture of the small intestine disease is almost the same. Symptoms are expressed by diary, ration, meteorism, stomach pain. There are changes in the chair: a large amount of mucus, remnants of untapped food. He is abundant, can be several times a day, but there is no blood in it in most cases.

The most common diseases of the small intestine include enteritis, which is in inflammatory character, can flow in acute or chronic form. The cause of its development is the pathogenic flora. With timely adequate treatment, digestion in the small intestine is restored in a few days. Chronic enteritis is able to cause intracean symptoms due to impairment of the suction function. The patient may have anemia, total weakness, weight loss. Deficit folic acid And the vitamins of the group B are the causes of the appearance of glossitis, stomatitis, borrowed. The lack of vitamin A causes a violation of twilight, dry the cornea. The lack of calcium is the development of osteoporosis.

Rip the small intestine

The small intestine is most susceptible to traumatic damage. Contribute to this significant length and insecurity. In 20% of cases of the small intestine, its isolated gap occurs, which often arises against the background of other traumatic damage to the abdominal cavity. The reason for its development is most often a rather strong straight blow in the stomach, as a result of which the intestines hinges are pressed against the spine, the pelvis bones, which causes damage to their walls. The gap of the intestine is accompanied by significant internal bleeding and the shock state of the patient. Emergency surgical intervention - The only method of treatment. It is aimed at stopping bleeding, restoration of the normal intestinal passability and careful sanitation of the abdominal cavity. The operation must be carried out on time, after all, ignoring the gap can lead to a fatal outcome as a result of a violation of digestive processes, abundant blood loss and the appearance of serious complications.

In the human body there is a small intestine located between the stomach and a large intestine. The channel of the small intestine is involved in the process of processing food.

The density of the intestine participates in an important process Mastering food.

Gastrointestinal

Brief input to anatomy. The small intestine is the first, the longest section of the gastrointestinal tract of a person who is the laboratory of the body. Externally, the channel of the small intestine looks like a tube, the length of which is from 2 to 4 meters. The diameter of the small intestine is imperceptibly narrowed, first it is 4 - 6 cm, then 2.5 - 3 cm. The small intestine starts from the sphincter of the stomach, ends with the transition to a thick intestine.

Uploading a secretion participating in the process of digestion throughout the organ. In the department digestive tract, under the influence of chemical elements, secreted by the intestines, pancreas and spleen, the preliminary splitting of the eating food on energy, construction substances is carried out. Here the chemical processing of the food mass is ends. Mixing and moving the food mixture helps regular cuts of muscles in the walls of the organ.

The structure of the subtle intestine

In the small intestine, the whole length is divided into departments. According to the anatomy of the body, three parts are distinguished.

Duodenum

The duodenum is an initial portion, a length of 21 cm (12 of the index fingers). The duodenal loop covers the pancreas, visually similar to the letter "C". The plot consists of four parts:

• ascending;
• descending;
• horizontal;
• top.

The upper part begins the organ near the sphincter of the stomach - loop, with a length of about 4 cm. It gradually goes into a downward, which envelopes the main organs: liver, bile duct. Further goes down, adhering to the right side. At the level of the third vertebra of the lumbar hotel turns to the left, creating a lower bend, surrounding the liver, kidney. The total length of the descending part is about 9 cm. In the same place, ranging from the pancreas and to the descending part, there is a biliary duct. Together with pancreatic, they enter the delicate intestine through the nipples.

The next site fills the cavity near the third lumbar vertebra in a horizontal position. Going up turns into ascending.
Ascending department - imprisoner. Fixing to the muscle partition, at the height of the second vertebra, is curved sharply, goes into a significant intestine. Nearby are a mesenteric vein, artery and abdominal gap of aorta.

Jejunum

At the top of the permane on the left side is occupied by the intestine. It consists of 7 loops, which in front closes a large gland. Behind, they are adjacent to the thin wall of the abdominal cavity.

Ileum

On the right side, at the bottom of the abdominal cavity is filled with the third department, duration up to 2.6 meters. The final loops descend into the deepening of the small pelvis, adjacent to the urinary, the urine and the concluding part of the digestive tract (the rectum).

The type of the design of the skinny and iliac parts are similar, serve as a connecting fold of the fine intestine. The perch is completely covered by the perma, thanks to her plasticity, it is attached to the back of the abdomen.

Anatomy of the walls of the organ

The structure of the walls is the same in the entire organ, except the duodenum. Consider in detail how many layers at the walls:

• Mucous. The structure of the inner shell is special, characteristic only by the thin walls of the intestine. Duodenal folds, villi and tubular deepening - anatomy of the walls of the organ. The mucous membrane of the small intestine over the entire surface is covered with folds, which perform in its lumen by 1 cm. At the end of the fold organ less, the distance between them is greater, but they are not aligned even with a filled tube. The bends are formed mucosa and submucosal. On the entire surface of the folds, there are vile between them formed from the mucous membrane. Millionthic grows covers the epithelium in which suction cells are located. Cells are firmly connected, and the mucus produced by them helps the movement of the food mass. In the growth of the vessels that provide blood supply, nerve endings. The center passes the capillary, which is connected to the capillaries of the submembrance. Muscular cells were concentrated near them, which are reduced during digestion, and the villi changes in the amount (thicken, lengthen or shorten). The allocated content enters the overall blood stream. With relaxed Miotic cells, grows straightened, expand, and all nutrient elements fall into the vessels. Among the growing glands are located, at the base of which is the foundation of secretion. It produces enzymes that update the epithelium glands in 5 to 6 days.
• Sublifting. In the layer connecting the mucous membrane and the miotic layer, there are cells of adipose tissue, nerve fibers, vascular plexus. In the structure of the duodenal sector are added secretion glands.
• Muscular. Inner and outer layers of muscle tissue create a surface shell. The interlayer between them, which is responsible for the motorcy, is nervous connections. Motoric muscles is represented by wave-like, rhythmic contractions affecting the proximal department to the anal hole. Vibration moves, mixing throughout the path partially digested food. The reducing is responsible for the vegetative nervous system, the relaxation zones and muscle contractions alternate.
• Serous. The small intestine is covered with a connective serous film. Only the duodenum is covered with film only before.

1. From the course of the anatomy to recall the anatomical and topographic features of the fine and colon and the main physiological processes occurring in them.

2. Repeat the structure of the single-layer epithelium, structure and histochemical characteristics of the mucous and glazed serous cells, the structure and the value of lymphatic nodules.

The purpose of the lesson: the study of the microscopic and ultramicroscopic structure and the histological and large intestinal estate.

SMALL INTESTINE

Anatomically in the small intestine is distinguished by a duodenum intestine, a mushroom and an ileum. In the small intestine proteins, fats, carbohydrates are subjected to chemical processing.

Development

The duodenum is formed from the final department of the front integer department of the middle, the loop is formed from these adventures. Skinny and iliac formulate from the remaining part of the middle intestine. 5-10 Development Weeks: The loop of the growing intestine is "pushed out" from the abdominal cavity in the umbilical cord, and the mesentery will grow to the loop. Next, the hinge of the intestinal tube "returns" in abdominal cavity, its rotation and further growth occurs. Epithelium Village, crypt, duodenal glands are formed from the administrator of the primary intestine. Originally single-row cubic epithelium, 7-8 weeks-one-layer prismatic.

8-10 week-formation of Village and Crypt. 20-24 weeks appearance of circular folds.

6-12 week-differentiation of epithelocytes, bonded epithelocytes appear. Beginning of the fruit period-formation of glycicalis.

5 weeks and differentiation of glazing exocrinocytes, 6 weeks and endocrinocytes.

7-8 week-formation of the mesenchyma of its own plate of the mucous membrane and submucosal base, the appearance of the inner circular layer of the muscular shell. 8-9 weeks - the appearance of the outer longitudinal layer of the muscular shell. 24-28 weeks muscular mucosal plate arises.

The serous shell is laid at 5 week embryogenesis from mesenchym.

The structure of the small intestine.

In the small intestine, the mucous membrane is distinguished, the subliminate base, muscle and serous shell.

The structural functional unit of the mucous membrane is intestinal villi-absorption of the mucous membrane, freely walking into the intestinal lumen and crypt (gland) -thnolation of the epithelium in the form of numerous tubes located in the liner of the mucous membrane.

Mucous membrane It consists of a single-layer prismaite-sided epithelium, its own layer of mucous membrane and muscle mucosa layer.

In the epithelium, several cell populations are distinguished: columnar epithelocytes, glazing exocrinocytes, exocrinocytes with acidophilic granules (Patenet cells), endocrinocytes, M cells. The source of their development-stem cells located at the bottom of the crypt from which precursor cells are formed. The last, mothotically divided, then differentiated into a specific view of the epithelium. Previous cells, while in crypts, move in the process of differentiation to the top of the villus. Those. Epithelium Crypt and Village represents a single system with cells at different stages of differentiation.

Physiological regeneration is ensured by mitotic division of precursors. Reparative regeneration - the epithelial defect is also eliminated by the reproduction of cells, or - in the case of coarse damage to the mucous membrane - is replaced by the connecting and wanted scar.

In the epithelial layer in the intercellular space there are lymphocytes carrying out immune protection.

An important role in the digestion and suction of food is played by the Crypt-Villanka system.

Intestinal Village– from the surface is lined with a single-layer prismatic epithelium with three main types of cells.

Stroll (carbonated) Vile epithelocytes - on the apical surface formed by microwaves a running kaim, at the expense of which the surface of the suction increases. In the microwave, thin filaments, and on the surface of the glycocalix, represented by lipoproteins and glycoproteins. In plasmolem and glycicalce, the high content of enzymes involved in the splitting and transport of suction substances (phosphatases, aminopptidases, etc.). The most intensively splitting and suction processes occur in the region of a worn outage, which received the name of the cluster and membrane digestion. The terminal network contains actin and myosine philants available in the apical part of the cell. Here are the connecting complexes from dense insulating contacts and adhesive belt, which connect neighboring cells and close the message between the intestinal lumen and intercellular spaces.

Under the terminal network there are tubes and tanks with a smooth endoplasmic network (fat absorption processes), mitochondria (energy supply of suction and transport of metabolites).

In the basal part of the epithelialocyte - the core, the synthetic apparatus (ribosomes, granular EPS). Lizosomes and secretory vesicles formed in the area of \u200b\u200bthe Golgi apparatus are moved to the apical part and are located under the terminal network.

Between the basal parts, wide intercellular spaces (characteristic of the epithelials involved in the fluid transport) between the lateral plasmolemmas of the neighboring cells on which there are folds and processes connecting with adjacent cells. Collaving, folds increase the volume of the intercellular space.

The secretory function of enterocytes: products of metabolites and enzymes needed for tribrous and membrane digestion. Synthesis of products-in granular EPS, the formation of secretory granules-in the Golgi apparatus.

Initial digestion, carried out on the glycicalce of bonded enterocytes is about 80-90% of the total digestion (the rest-digestion). Priest digestion passes in aseptic conditions and is highly conjugate.

M-cells-Lesters with microscopes, a type of columnar (cached) enterocytes. Locked on the surface of peyer plaques and single lymphatic follicles. On the apical surface of microslipping, with which macromolecules from the intestine are captured, endocytosis vesicles are formed, which are transported to the basal plasmolem, and then in the intercellular space.

Box-shaped exocrinocytes Arranged one among the columnal cells. To the final division of the small intestine, their number increases. Changes in cells are cyclically.

The accumulation phase of the core accumulation is pressed to the ground, near the kernel of the Golgi and Mitochondria apparatus. In the cytoplasm over the core of the drop of mucus.

The formation of the secret occurs in the Golgi apparatus. In the accumulation stage of mucus in the cell modified mitochondria (large, bright with short crystami).

After the secretion of the secret, the Balo-shaped cell is narrow, there are no granules in the cytoplasm. The surveyed mucus moisturizes the surface of the mucous membrane, facilitating the promotion of food particles.

Under the recreation epithelium there is a basal membrane, behind which a loose fiber connecting tissue of its own plate of the mucous membrane. It takes the blood and lymphatic vessels. Blood capillaries are located under the epithelium. They are visceral type. Arteriol, Venula and lymphatic capillary are located in the center of Vilkins. There are separate smooth muscle cells in the stroma, the beams of which are wrapped with a network of reticular fibers that bind them with a stroma villus and a basal membrane. The reduction of smooth myocytes provides a "pumping" effect and enhances the absorption of the contents of the intercellular substance into the clearance of capillaries.

Proteins and polypeptides on the surface of the microwaves of the columns enterocytes are digested to amino acids. Actively sucking, they fall into the intercellular substance of their own plates of the mucous membrane, from where they diffuse into the blood capillaries.

Carbohydrates are digested to monosachar. Also actively absorbed and entered into the blood of visceral type capillaries.

Fats are split to fatty acids and glycerides. Captured by endocytosis. In enterocytes, they endogenize (change the chemical structure in accordance with the body) and reinterests. Transport of fats is carried out by the advantage of lymphatic capillaries.

Intestinal Crypt. Contains stem cells, precursor cells, differentiable cells at different stages of development, columnar epithelocytes, glassoid exocrinocytes, endocrinocytes and PAnet cells.

Star epithelocytes Make up the bulk of epithelial cells. Thin barreled cut, lower, basophilic cytoplasm.

Box-shaped exocrinocytes- The structure is similar to those described in Vorcink.

Patenet cells Arranged or groups at the bottom of Kripte. The bactericidal substance is secreted - lysozyme, antibiotic polypeptide nature - defense. In the apical part of the cell, strongly refractive light, sharply acidophilic when painting the granules. They are protein-polysaccharide complex, enzymes, lysozyme. In the basal part of the cytoplasma basophilic. In cells, a large amount of zinc, enzymes - dehydrogenases, dipeptidases, acid phosphatase were revealed.

Endocrinocytes.There are more of them than in Villas. The EU cells secrete serotonin, motilin, substance R. A-cell-enterogluclugon, S-cell-secretin, I-cells - cholecystokinin and pancreatimine (stimulate the functions of the pancreas and liver).

contains a large number of reticular fibers forming the network. Cross-grained cells with fibroblastic origins are closely related to them. There are lymphocytes, eosinophils, plasma cells.

Muscle plate mucousit consists of internal circular (individual cells are deployed into the own plate of the mucous membrane), and the outer longitudinal layers.

Sublifier baseformulated with loose fibrous unformed connective tissue and contains fat tissue slices. It contains vascular collectors and sublifting nervous plexus .

Muscular shell. Internal circular and outer longitudinal layers of smooth muscle tissue. Between them a layer of loose fiber junction tissue, where the vessels and nodes of the nervous muscular and intestinal plexus. It makes mixing and pushing the chimus in the goal.

Serous sheath.Covers the intestine from all sides, with the exception of the duodenum, covered with peritoneum only in front. It consists of a connecting and wanted plate (PCT) and a single-layer, flat epithelium (mesothelium).

Duodenum.

A feature of the structure is the presence of a duodenal gland in a submucosal basis is alveolar-tubular, branched glands. Their ducts open into the crypts or at the base of the villi directly into the cavity of the intestine. Glandulocytes of end departments-typical mucous cells. The secret is rich in neutral glycoproteins. In glandulocytes, synthesis, the accumulation of granules and the elimination of the secret is noted. Secretary function: digestive-participation in the spatial and structural organization of the processes of hydrolysis and suction and protective-protects the intestinal wall from mechanical and chemical damage. The lack of secrecy in Himus and the closed mucus changes their physicochemical properties, while the sorption capacity for the endo and ex-hydrolazes and their activity are reduced.

The duodenum opens the liver and pancreatic ducts.

Cluster of lymphoid fabric in the small intestine in the form of lymph nodules and diffuse clusters (peyer plaques). Single all over, and diffuse - more often in the ileum. Implement immune protection.

Vascularization.The arteries form three plexuses: intertensive (between the inner and outer layer of the muscular shell), wide-flush-in a submucosal basis, narrow-natal-in the mucous membrane. Viennes form two plexus: in the mucous membrane and a submucosal basis. Lymphatic vessels - in the intestinal cessinka centrally located, blindly ending capillary. From it, the lymph is subject to the lymphatic weaving of the mucous membrane, further to the subliminate base and in the lymphatic vessels located between the layers of the muscular shell.

Innervation. Afferent - muscular and intestinal plexus, which is formed by sensitive nerve fibers Spinal ganglia and their receptor endings. The efferent-thicker wall is a parasympathetic muscular-intestinal (most developed in the duodenum) and submembrance (Maisner) nervous plexus.

Digestion Includes further enzymatic treatment of substances to finite products, their preparation for suction and the suction process itself. In the cavity of the intestine, extracellular weight digestion, near the intestine wall-closed, on the apical parts of the plasma-membrane plasmolemma and their glycicalcese-membrane, in the cytoplasm enterocyte-intracellular. Under suction, they understand the passage of products of the final splitting of food (monomers) through the epithelium, basal membrane, vascular wall and their flow in blood and lymph.

Check questions and tasks

1. Transfer morphofunctional features of the small intestine.

2. How the structure has villi and crypts of the small intestine. What functions do they perform?

3. The package of the structure of the mucous membrane in different departments of the small intestine.

4. Transfer digestive types in different bowels.

1. What cells in the epithelium of the Village take part in the trim digestion?

2.U patient with extensive cutany wounds Belly is damaged epithelium mucosa mucosa. Due to what cells will regeneration be carried out?

3. The electronic micrographs of the epithelium of the small intestine are visible cells with secretory granules. In some cells, they are electronically dense and are located in the apical part of the cytoplasm, in other-smaller and focused in the basal pole of the cells. What is the names of the cells where they are localized and what is their function?

COLON.

Anatomically in the colon is distinguished by a blind intestine with a worm-like process, an upward, transverse, downward and sigmoid rim and straight intestine. In the colon there is absorption of electrolytes and water, digestion of the fiber, the formation of hiding masses. The secretion of hot cells of a large amount of mucus contributes to the evacuation of the carts. With the participation of intestinal bacteria in the colon, vitamins in 12 and K. are synthesized

Development.The epithelium of the colon and the pelvic part of the rectum is the derivative of the Entoderma. It grows on the 6-7 week of intrauterine development. Vile and crypts are laid at the same time. With the growth of the surface of the mucous membrane, the villus are stretched and smoothed. The muscle plate of the mucous membrane develops for 4 months of intrauterine development, and the muscular shell is somewhat earlier - for 3 months.

Colon.The wall is formed by the mucous membrane, the submissible base, muscular and serous shells. The relief is characterized by the presence of circular folds and intestinal crypt. There are no vile.

Mucous membrane It has three layers - epithelium, own plate and muscle plate.

Epitheliumsingle-layer prismatic. Contains three types of cells. Star epithelocytes On the surface of the mucous membrane and in its crypts. Similar to those in the small intestine, but have a more subtle run-down car. Box-shaped exocrinocytes It is contained in large quantities in the crypts, the mucus is distinguished. At the base of intestinal crypt, undifferentiated epitheliocytes are underway, due to which the regeneration of columnar epithelocytes and glass-like exocrinocytes occurs.

Owl plate mucous membrane - Typical connecting and intrinsic layers between the crypts. There are single lymphatic nodules.

Muscular mucosa plateexpressed better than in the small intestine. The outer layer is longitudinal, muscular cells are located more loose than in the internal circular.

Subliminate base.Many fat cells. Vascular and nervous submembratus plexuses are located. Many lymphoid nodules.

Muscular shell. The outer layer is longitized, assembled in the form of three tapes, and between them a small number of beams of smooth myocytes, and internal-circular. Between them loose fibrous connective tissue with vessels and nervous muscular-intestinal plexus.

Serous sheath.Covers different departments of unequal (fully or from three sides). Forms growing, where fat fabric is located.

Appendix. Carries out a protective function. Characteristic is the presence of lymphoid tissue. It has a lumen. The intensive development of lymphoid tissue and lymph nodules is noted on the 17-31 week of intrauterine development.

Mucous membrane It has crypts covered with single-layer prismatic epithelium with a small content of glass-shaped cells.

Own plate mucouswithout a sharp boundary, it turns into a submembratus base, where numerous large clusters of lymphoid tissue are located. IN sublifting basedblood vessels are located and sublitty nervous plexus.

Muscular shellit has an outer longitudinal and internal circular layers. Outside Appendix is \u200b\u200bcovered serous shell.

Rectum.

Wall shells are the same.

Mucous membrane.Consists of epithelium, own and muscle plates. Epitheliumin upper Department Single-layer, prismatic, in the columnary zone-multi-layer cubic, in the intermediate-multi-layer flat, non-illuminating, in the skin-multilayer flat ornamental. In the epithelium there are columnar epithelocytes with a barreered car, glass-shaped exocrinocytes and endocrine cells. The epithelium of the top of the rectum forms the crypts.

Own record Participates in the formation of folds of the rectum. Single lymph nodes and vessels are located here. A columnar zone-lies with a network of thin-walled blood lacuna, the blood of them reaches the hemorrhoids of the veins. Intermediate zone - many elastic fibers, lymphocytes, tissue basophils. Single sebaceous glands. Skin zone-sebaceous glands, hair. Pottle glands of apocryne type appear.

Muscle plate The mucous membrane consists of two layers.

Subliminate base.Nervous and vascular plexuses are located. Here is the plexus of hemorrhoidal veins. In case of violation of the tone of the wall in these veins, varicose extensions appear.

Muscular shellit consists of an external longitudinal and internal circular layer. The outer layer is solid, and the internal thickening form the sphincters. Between the layers of the layer of loose fibrous unformed connective tissue with vessels and nerves.

Serous shell covers the rectum in the upper part, and in the lower departments, the coupling shell.

Questions for self-control:

1. Keep the general plan for the structure of the colon wall. What are the estimated features of its mucous membrane?

2. Why is the muscular sheath of thin and colon?

3. Function of a worm-like process, the principles of its structure.

1. The patient's liver pathology in the patient sometimes introduces medicinal substances with the help of enema. What types of cells in the epithelium mucous membrane of the colon are absorbed medicinal substance?

2. On the basis of which histological signs Can I distinguish a black-shaped process on the presented micrographs?