Pathologic

physiology of digestion and liver

Insufficiency of digestion. The reasons. Manifestations

• The basic role of digestive system consists in digestion of components of food that get into a alimentary chanel (proteins, fats, carbohydrates), absorption of formed nutrients and removing from an organism some end-products of metabolism. Numerous functions of digestive system are adjusted by the central and vegetative nervous system, humoral and endocrine influences. Disorders of regulation entail Disturbance of normal current of the processes in an alimentary channel, result in insufficiency of digestion and promote development of many diseases.

• Insufficiency of digestion is a pathological condition at which the digestive system does not provide assimilation of the nutrients that get inside the organism. As a result starvation can develop.

• Depending on ethiology there are

• hereditary caused (some kinds malabsorption)

• acquired insufficiencies of digestion

Cause the development of insufficiency of digestion

• 1. Alimentary (food) factors: • a) reception of bad and rough food • b) live on dry rations • c) irregular reception of food • d) disbalanced meal (for example, reduction of the

maintenance of vitamins, proteins in a diet)• e) overindulge in alcohol• 2. Physical factors • Among factors of this group the greatest role belonge

to radiation which effect epitheliac cells of the alimentary channel which have high mitotic activity

• 3. Chemical agents • Are the reason of disorders of digestion after

poisonings with inorganic and organic connections during manufacture and in life.

• 4. Biological factors: • a) bacteria (for example, v.cholera, causative

agents dysentery, a belly typhus, paratyphus) • b) bacterial toxins (for example, at salmonellosises,

a staphylococcal infection) • c) viruses (for example, adenoviruses) • d) helminths• 5. Organic effects: • a) congenital anomalies of digestive system • b) postoperative conditions • c) tumours of digestive system

• 6. Disorders nervous and humoral regulation. Disorders of digestion can develop during:

• a) psychoemotional disorders (neurotic and neurosis-like conditions)

• b) mental diseases (schizophrenia, a manic - depressive syndrome)

• c) organic diseases of the central nervous system (encephalites)

• d) lesions of peripheral structures of vegetative nervous system

• e) reflex disorder (various viscero-visceral reflexes) • Disorders of humoral regulation of digestion may

be connected to disorders of synthesis and secretion gastrointestinal hormones (gastrine, secretin, cholecystokinin-pancreazymin etc.)

Insufficiency of digestion may be shown by the following syndromes:

• 1. Starvation

• 2. Dispeptic syndrome

• 3. Dehydratation

• 4. Disturbance of the acid-basic balance

• 5. Intestinal autointoxication

• 6. The painful syndrome

• Dispeptic syndrome includes different combinations of the following symptoms:

• a) anorexia

• b) heartburn

• c) eructation

• d) nausea

• e) vomitting

• f) meteorism

• g) constipations

• h) diarrhea

• Anorexia is a full absence of appetite while person need food

• It is pick out the following kinds anorexia:• а) intoxical - develops during acute and chronic

poisonings (for example, salts of mercury, medical products, bacterial toxins)

• b) dispeptic - arises at diseases of digestive system, has more often behavior-reflex nature

• c) neurodynamic - develops as a result reciprocal of braking the centre of appetite after overexcitation of separate structures limbic systems (for example, a painful syndrome during a heart attacks, colics, a peritonitis)

• d) neurotic - it is connected with excessive excitation of cortex of brain and strong emotions (especialy with negative)

• e) psychogenic – is connected with conscious restriction of food (for example, with an aim of getting thin or as result of mental disorders)

• f) neuroendocrinopathy - it is caused by organic lesins of the central nervous system (hypothalamus) and endocrine diseases (hypophysial cachexia, Addison’s disease)

Two mechanisms of anorexia development :

• 1) reduction of excitability of the food centre (intoxical, dispeptic, neuroendocrinopathy anorexia)

• 2) braking of neurons of food centre (neurodynamic, neurotic, psychogenic anorexia)

• The heartburn is a feeling of heat or burnings long gullet. Its development is connected with irritation of receptors of a gullet during pelting contents of a stomach into a gullet (reflux).

• It may be caused by:

• а) a plenty of formed gastric juice

• b) functional insufficiency of cardial sphincter

• The eructation is a sudden involuntary allocation into oral cavity some gas from a stomach or a gullet, sometimes with small portions of contents of a stomach

• The increasing of the contents of gases in stomach may be caused by two reasons:

• а) receipt big quantity of gases with food and a drink (for example, aerated drinks), siping of air (aerofagia)

• b) formation of gases in the stomach, it is especial at a long delay there peep (at a stomach ulcer, cancer of a stomach)

• As a result of increasing of the contents of gases in a stomach it is increased intrastomach pressure. It reflexly can cause:

• а) reduction of muscles of a stomach wall • b) a spasm of the gatekeeper • c) a relaxation of muscles of aesophagal-gastric sphincter• Thereof gases are superseded from a cavity of a stomach in

a gullet, to a drink. And then in an oral cavity

• The nausea is a burdensome sensation in epigastric area breast and in the oral cavities, quite often previous to vomitting and frequently accompanying with the general weakness, sweatness, increasing of salivation, coldness of arms and legs, pallor of a skin, decrease of arterial pressure that is connected to activation parasympathic nervous system. In a basis of a nausea is an excitation of the emetic centre, but insufficient for occurrence of vomitting lays.

• Vomitting - the complex-reflex act which results to eruption of contents of a stomach outside through a mouth is a result of excitation of the emetic centre which is situated in an oblong brain.

• The mechanism of vomitting includes a number of consecutive stages. His pick out the following pathogenetic variants of vomitting:

• а) central - it is connected with increasing of excitability of the emetic centre. It happens at diseases of the central nervous system (meningitises, encephalities, tumours of a brain), at excitation of cortex of the big hemispheres (behavior-reflex vomitting) or receptors of a labyrinth (vestibular vomitting);

• b) hematogenic-toxic - it is caused by direct action of toxic substances which are in blood, on receptors that are in emetic centre. It may be exogenous substances (carbonic oxide, alcohol, medical products, toxins of bacteria) or toxic products of an own metabolism which are collected during at a uremia, hepatic insufficiency, decompensated diabetes and others;

• c) visceral (reflex) – is a result of reflexes which are caused from different receptors of internal organs. Such reflexogenic zones are in a stomach, a mucous membrane of pharynx, coronal vessels, peritoneum, biliary duct etc.

• Meteorism is a superfluous accumulation of gases in the digestive channel due to their increased formation or insufficient removing from intestines

• Superfluous formation of gases underlies development of the following kinds of meteorism:

• а) alimentary - develops at reception with food a lot cellulose, starches (leguminous, cabbage, a potato)

• b) at disorders of digestion (pathology of enzymes, disturbances of absorbtion, intestinal disbacterioses)

• Disturbance of discharge of gases typically for such meteorism:

• а) mechanical - develops as a result of Disturbance of passableness of intestines (spasms, solderings, tumours)

• b) dynamic - arises at disorders of motor function of intestines

• c) circular – is a result of the general and local disorders of blood circulation

• It is pick out two mechanisms of development of constipations - spastic and atonic.

• The first is caused by long constant reduction of smooth muscles of guts, the second – because of their atonia.

• To spastic constipations concern:• а) inflammatory - arise owing to local spastic

reflexes with changed of mucous membrane;• b) proctogenic - develop at a pathology

anorectal areas;• c) mechanical - arise at impassability of guts;• d) toxic – is result of poisonings lead, mercury,

thallium.

• Atonic constipations are:• а) alimentary - develop at receipt light food

containing(not enough) cellulose• b) neurogenic – is the result of disorders of

nervous regulation of a motility of guts• c) hypodynamic - arise at bed patients, at old men,

people with very low motor activity• d) constipations at anomalies of a thick gut

(Girshprungs disease)• e) constipations in consequensce disorders water-

electrolyte metabolism

• Diarrheas are often empty of guts with discharging of diluted and plentiful excrements.

• Pathogenetic variants of diarrheas:• а) osmotic diarrhea. Develops when osmotic pressure is

increase because of intestinal contents at intake of substances which are bad or are not absorbed at all (for example, laxative), and also at disturbances of digestion and absorbtion (syndromes maldigestion and malabsorbtion)

• b) secretory diarrhea. It is connected with activation of secretion of ions (Na+ , Cl‾), that causes the strengthened secretion of water into gap of guts (for example, during cholera)

• c) diarrhea, caused by braking of active transport of ions through cellular membranes in guts (for example, congenital chlordiarrhea - genetic defect of absorbtion of anions of chlorine in illeum)

• d) diarrhea is caused by increase of permeability of an intestinal wall (inflammatory)

• e) diarrhea at disturbance of an intestinal motility

• Intestinal autointoxication, as a rule, is connected with infringement corelation between bacterias and formation a plenty of toxic products of fermentation and putrafaction.

• Dysbacteriosis is an infringement of a ratio between separate kinds of microflora. Thus the quantity of the bacteria causing processes of putrafaction and fermentation is frequently increased. As a result formation in guts of toxic products - hydrogen sulphide, scatol, indole, phenols, putrescine, cadaverine grows etc. If formation of these products exceeds functional ability of a liver on them detoxifcation, attributes of hepatic insufficiency develop. Development of intestinal autointoxication is promoted by reduction of intestinal peristalsis(constipations), reduction of secretion of intestinal juice, intestinal obstruction.

• The pain frequently accompanies with development of diseases of the alimentary channel. Depending to the reasons and pathogenesis pain may have different characters.

• Distinguish the following mechanisms of occurrence of a pain at lesions digestive organs:

• The spastic mechanism. The pain is caused by a spasm of smooth muscles of different departments of the alimentary channel. It is considered, that in this case the reason of a pain is constriction of the vessels which are laying in the wall of hollow organs owing to what the ischemia develops. It cause appearance of the products of metabolism from the working organs, and their influense on pain receptors. At sharply arising strong spasm pains on colics type develops

• The hypotonic mechanism. At reduction of a tone of smooth muscles (hypotonia) the pain appears from a stretching the wall of hollow organs (a stomach, guts, gall bladder) by their contents. Thus the mechanical stretching of tissues causes irritation of the nervous endings;

• Influence of biologically active substances (histamine, serotonin, kinines, prostaglandins) on the nervous endings. These substances formes and secretion at damages of cells and inflammation (gastritises, duodenities, enterities, colics, cholecystitises). Especially a lot of these substances appear during acute pancreatitis.

In a basis of indigestion the following disturbances of functions of digestive

system may take place:• 1. Disturbance of secretion in digestive system:• а) hypersecretion conditions: • 1 hypersalivation • 2 gastric hypersecretion • 3 pancreatic hypersecretion • 4 hypercholia• b) hyposecretion conditions: • 1 hyposalivation • 2 gastric hyposecretion • 3 pancreatic hyposecretion • 4 acholia

• 2. Disturbance of motor function of the alimentary channel:

• 1 disturbance of chewing • 2 disturbances of swallowing - dysphagia • 3 gastric dyskinesias • 4 intestinal dyskinesias • 5 dyskinesia gall bladder and biliary ducts

• 6 disturbances defecation• 3. Disturbance of absorbtive functions - a

syndrome malabsorbtion.

Disturbance of functions of a stomachDisturbance of secretion of a hydrochloric

acid, pepsin, mucus• Hydrochloric acid is excreted by parietal cells of a mucous

membrane of a stomach which number in the healthy person is about 1 billion. Secretion of it is adjusted by difficult mechanisms which include three interconnected phases of secretion: neurogenic (vagal), gastric (gastrine) and intestinal which is regulated by irritation of receptors and intestinal hormones.

• In regulation of functional activity of parietal cells takes place nervous system (through mediator acethylcholine), and also various hormones (serotonin, insulin). The basic mechanisms of regulation the functions of parietal cells of stomach can be presented as follows. The parietal cell contains receptors to histamine which is released from enterochromaphilic cells (ECL), gastrin and cholecystokinin (CCK-receptors), and also receptors for acethylcholine (M3-receptors),

• Stimulation of H2-histamine receptors is bring on formation cAMP, and stimulation of CCK-receptors and M3-receptors results to increasing of a level of endocellular calcium (Са++). Stimulation of M3-receptors increases, not only comming Са++ into a cell and due to increasing of level inositolthreephosphate (IP3) strengthens an output of endocellular Са++. Gastrin, cholecystokinin and histamine also raise output of Са++ due to action on IP3 . Parietal cell has a receptor for prostaglandin E2 (PGE2)) which stimulation reduces a level cAMP and results in braking secretion of hydrochloric acid.

• Secretion of a hydrochloric acid by parietal cell is carried out by a principle of the proton pump in which K+ exchanges on Hˉ‾, and Cl‾ on HCO3‾. An important role in this process plays H+, K+ -ATPase which, using energy of ATP, provides transport H+ from parietal cells and K+ into the cell. The difficult mechanism of regulation the production of hydrochloric acid explains increasing or decreasing of its secretion under the influense of numerous factors.

• Hypersecretion of a hydrochloric acid plays the important role in development of sevsral gastroenterologic, may be observed at is hereditary caused increasing of weight parietal cells, the increased tone of a vagal nerve, a stretching of antral part of a stomach during disorder of emptying, increasing of secretion of gastrin, increasing quantity of ECL-cells in the mucous membrane of a stomach (at patients with carcinoid syndrome).

• Besides a hydrochloric acid by the main cells of a mucous membrane of a stomach it is formed pepsin from pepsinogen. Now distinguish seven types of pepsinogen. Disturbance of pepsin formation functions of a stomach matters in appearance of number gastroenterologic diseases (for example, a stomach ulcer).

• Gastric mucus is secreted by mucous cells of a mucous membrane of a stomach. Into structure of gastric musous enter glycosaminoglycans and glycoproteins. From sialic acids N-acethylneuraminic acid provides ability of gastric mucus to form a water-insoluble viscose coverings mucus membrane of a stomach. Secretion of gastric mucus takes place continuously. Stimulating influence on formation of mucus render irritation adreno- and cholinoreceptors, prostaglandins. In process of mucus formation the certain role plays stability of lisosoms. Hydrolasis of lisosoms cause dehydratation of glycoproteins.

• Gastric mucus (together with bicarbonates) takes part in formation of a mucus barrier which supports a gradient рН between a hollow of a stomach and its mucus membrane and late H+.

• Disturbance of this barrier as a result of reduction the synthesis of prostaglandins in the wall of a stomach is one of mechanisms of damage mucus membrane under action of some medical products (aspirin, not steroid anti-inflammatory drugs). On the contrary, synthetic prostaglandins have cell protective properties, raise mucus formation and prevent effect of a stomach.

Gastric hypersecretion is characteristed by:

• Increasing the quantity of gastric juice as after reception of food, and also on the empty stomach

• Hyperaciditas and hyperchlorhydria - is increasing of the common acidity and the maintenance of a free hydrochloric acid in gastric juice

• Increasing of digestive ability of gastric juice

• The disturbances of digestion connected with gastric hypersecretion, are caused by a long delay food in the stomach (pilorus is closed, because neutralization of very sour contents that goes into duodenal gut, demands a lot of time).

• This circumstance has such consequences:• in guts enter not enough contents that results in

reduction of peristaltics of guts and to development of constipations

• in the stomach processes of fermentation and formation gases amplify. It causes appearance of an eructation and a heartburn

• motor activity of a stomach is increased as the result hypertone and hyperkinesis of smooth muscles develops

Gastric hyposecretion is are characterised by:

• Reduction the quantity of gastric juice on an empty stomach and after reception of food

• Decreased or zero acidity of gastric juice (hypo-or unacidity), reduction of the contents in it or absence of a free hydrochloric acid (hypo- or achlorhydria)

• Reduction of digesting ability of gastric juice due to achylia (the full stop formation a hydrochloric acid and enzymes)

• Reduction of gastric secretion results in disturbances of digestion along alimentary channel.

• It is caused by insufficient formation of gastric juice that keeps pylorus opened also contents of a stomach quickly passes into a duodenal gut where environment becomes constantly alkaline. Thus there is a hinder of formation secretine as a result secretion of pancreatic juice is decreased and processes of hollow digestion in guts are broken.

• Insufficiently digested components of food irritate receptors of a mucus membrane of guts that results in their strengthening of peristaltics and diarrheas develop.

• Besides an absence of a hydrochloric acid in a stomach is leads to the grow of microflora in the stomach.

• Activation of processes of rotting and fermentation is connected with it in the stomach and appearance such Disturbance of diggestion, as an eructation, the impose tongue etc.

Disturbance of motor function of stomach

• Disturbance of motor function of stomach is called gastric diskinesia

• Trere is two kinds of gastric diskinesia: hypertonic and hypotonic

• Hypertonic kind is characterised by strengthening of peristaltics(hyperkinesia) and increasing of a tone of muscles of a stomach(hypertonia)

• The hypotonic kind, on the contrary, is characterized by a hypotonia and hypokinesia

The reasons of motor gastric disturbance of hypertonic type

• some food factors (rough food, alcohol)• increase of gastric secretion• increase of a tone of vagal nerve• some gastrointestinal hormones (motilin)• Hypertension and hyperkinesia of stomach leads to:• a long delay of food in stomach that promotes

increase of gastric secretion and development of ulcers on a mucus membrane

• development antiperistaltics of stomach that results in development of dispeptic disturbances (an eructation, a nausea, vomitting)

• One forms of diskinesia of stomach of hypertonic type is pylorospasm

• It is observed mainly in babies, especially in the first weeks and months of life.

• Pylorospasm in children is caused by functional disturbances of the nervous- muscular system of pylorus part stomach. It is observed mainly at the excitable children who have transferred intra-uterine hypoxia, born in asphyxia with attributes of a birth trauma of the central nervous system

• At pylorospasmis marked weak development of muscles in cardial parts of a stomach and its more expressed development in the area of pylorus. It promotes development of vomitting and eructation

Causes of stomach motor activity reduction • alimentary factors (fat food)• reduction of gastric secretion (hypoacid gastritises)• reduction of a tone of a vagal nerve• action overwhelming a motility of a stomach through

gastrointerstitial hormones (gastroingibitued peptide, secretine etc.)

• removal of pylorus part of a stomach• the common weakening of organism, an exhaustion,

gastroptosis• At hypotonic diskinesias time of staying of food in the

stomach is shortened that conducts to disturbance of its digestion. Action of the not digested components of food on receptors of a mucus membrane of guts causes the increase of peristalties and diarrheas.

The reasons and pathophysiologic mechanisms of a stomach ulcer

• The stomach ulcer is chronic relapsing disease which is characterized by formation of ulcer in a stomach and duodenum gut

• Ethiology of ulcer disease now residnally not established. It is considered, that in development of stomach and duodenal ulcers take place the following factors

• 1. Psychoemotional negative overstrains (negative emotions, disputed situations, feeling of constant alarm, overfatigue etc.)

• 2. Stress• 3. Hereditary predisposition • 4. The error in a meal – live on dry ration, irregular reception peep, eating

of rough or pungent food, bad chawing of food, fast meal, absence of the teeth, the insufficient maintenance(contents) in foodstuff of proteines and vitamins

• 5. Chronic gastritis and duodenitis with increased secretion of glands of mucus membrane

• 6.The microbic factor - Helicobacter pylori• 7.Deleterious habits - smoking, overindulge of alcohol

• According to modern representations, pathogenesis of stomach ulcer in general is reduced to disturbance of balance between factors acid-peptic aggressions of gastric contents and elements of protection of a mucus membrane of stomach and duodenalum. Sufficient development of bicarbonates, good regeneration of epithelial cells, the kept blood supply of a mucus membrane, normal formation and the maintenance of prostaglandins in a wall of a stomach, sufficient gastric formation of mucus are factors that protect mucus membrane.

• During last years an important role in weakening of protective properties of a mucus membrane of a stomach and a duodenum is given to microorganisms Helicobacter pylori. These bacterias produse a lot of enzymes (urease, protease, phospholipase), damaging a protective barrier of a mucus membrane, and also various cytotoxins. The most pathogenic are Vac A-stams, that produce vacuolization cytotoxin which results in formation cytoplasmatic vacuoles and destructions of epithelial cells, and the Sad A-stams which express gene associated with cytotoxin. This gene codes proteine which has direct damaging effect on a mucus membrane. Helicobacter pylori romotes liberation in a mucus membrane of a stomach interleukines, lisosomal enzymes, TNFα, that causes development of inflammatory processes in the mucus membrane of stomach. Pathophisiologic mechanisms of development of duodenum ulcer gut in 95 % of cases associated with Helicobacter.

• Contaminating the mucus membrane of the stomach by Helicobacter is accompanied by development superficial anthral gastritis and duodenitis and conducts to increasing a level of gastrin with the subsequent increasing secretion of a hydrochloric acid. The superfluous quantity of a hydrochloric acid, getting into a lumen of duodenum, in conditions of deficiency of pancreatic bicarbonates promotes development of duodenitis and besides cause appearance in duodenum sites gastric melatonin (reorganization of epithelial of duodenal mucus membrane on gastric type) which are quickly contaminated by Helicobacter. Further at adverse current, especially when there are additional ethiologi factors (hereditary predisposition, 0 (1) group of blood, smoking, psychological an overstrain etc.), In sites of metaplased mucus membrane ulcer defect is formed. However connection of occurrence of a stomach ulcer with infection of mucus membrane of stomach by Helicobacter revealed not always. Approximately 5 % of patients with ulcers of a duodenum gut and in 15-20 % of patients with stomach ulcers, disease develops without participation of these microorganisms.

Disturbance of intestinal functions

• Functions of intestines may be broken owing to many organic diseases. In some cases these disturbances arise owing to disturbances of nervous regulation of a motility of a small and large intestine

• Disturbance of digestion and absorbtion in intestines

• The complex of disturbances which appear in an organism as a result of disturbance of processes of digestion and absorbtion, has received the name of a syndrome maldigestion and malabsorbtion

The syndrome maldigestion

• The syndrome maldigestion are disturbances of primary digestion, caused by insufficient receiption into guts the digestive enzymes, in particular at pancreatic hyposecretion.This syndrome appearea in:

• disturbance of digestion of fats (absence of lipase and phospholipase). About 60-80 % of fat that get into guts is deduced with feaces – steatorrhea (fat in feaces)

• disturbance of absorbtion of fat-soluble vitamins – cause the development hypovitaminosis A, E and K

• disturbance of digestion of proteins (absence of digestive proteases). About 30-40 % of food protein are not acquired. In feaces there is a plenty of muscular fibres

• disturbance of digestion of carbohydrates (absence of amylases)

• disturbance of degrad of nucleinic acids (absence of nucleases)

The syndrome of malabsorption

• It is complex of symptoms which appearing results from disturbance absorbtion of substances in guts. Disturbance of absorbtion in guts may be caused by the disturbances that appeare at three levels:

• Preenterocytic disturbance. Develop as a result of disturbances of processes of digestion before absorbtion;

• Enterocytic. From disturbance of activity epithelial cells of intestinal mucus membrane;

• Postenterocytic. Are consequence of disturbance of the processes that provides receiption of soaked up substances into internal environment of an organism (blood, lymph).

Preenterocytic disturbances:

• Disturbances of motor function of the alimentary channel• Disturbances of primary digestion (a syndrome

maldigestion). By origin they may be gastrogenic, pancreatogenic, hepatogenic, enterogenic, disregulated, iatrogenic (connected with long usage of antibiotics and other medical products)

• Disturbance memrane digestion. More often they are caused by disturbances of formation and embedding of enzymes into plasmatic membrane of enterocytic microvillus

• Interstitial pathology of enzymes a hereditary caused disturbances of synthesis the digestive enzymes by microvillus which provide processes of membrane digestion. Among interstitial pathology of enzymes the most often is intolerance to disaccharides (lactoses, saccharoses, tregaloses) and insufficiency of peptidase (gluten enteropathy, celiac disease).

The reasons of malabsorbtion may be such enterocytic disturbances:

• reduction of absorbtion area (a condition after a resection of a gut, an atrophy of villus and microvillus)

• hereditary caused and acquired disturbance of formation of proteins - carriers monosaccharides (intolerance of glucose, galactose, fructoses), amino acids (tryptophanmalabsorbtion), ions of calcium (hypovitaminosis D)

• disturbances of functioning ions pumps of enterocytes (transport monosaccharides and amino acids is connected with work of Na-K-pump)

• deficiency of energy (absorbtion the majority of substances - process energydependent)

• disturbance of assembly in enterocytes of convey complexes (chilomicrones, lipoproteids)

The reasons of malabsorbtion may be such postenterocytic disturbance:

• Disturbances of blood circulation in a wall of guts, may be caused by disturbances of general haemodynamic in system v.reccurentis and local disturbances (ischemia, venous hyperaemia, thrombosis, embolia, reactions of vessels at an inflammation);

• Disturbances lymph flow. Except of general dosorders of lymph circulation they may be connected to disturbances of reduction of fibers of intestinal wall. Such reduction in norm is carried out due to local reflexes with a part of submucus nervous plexus and at participation of a hormone villikinin.

Disturbances of motor function of intestines

• Disturbances of motor function of guts refer to intestinal diskinesia.

• There are two types of intestinal diskinesia: hyperkinetic and hypokinetic.

• The first type is characterised by strengthening of the peristalties, segmentary and pendulum-like movements it has such manifastation as diarrheas.

• The second, on the contrary, is characterized by easing of motor activity of guts as a result constipations appears.

The reasons of intestinal diskinesias of hyperkinetic type:

Increasing excitability of receptors of guts to adequate irritators, that accompanies with development of an inflammation of a mucus membrane of intestines (enteritis, colics)

Action on receptors of guts unusual, pathological irritators - not digested food (for example, for achylia), products of rotting and fermentation, toxic substances etc.

Increasing of excitability of the centres of a vagal nerve Increase of form of some gastrointerstitial the hormones that

strengthening periataltics of guts (motilin) Consequences intestinal diskinesias of hyperkinetic type are: disturbances of digestion (digestion, absorbtion) dehydratation secretory not gas acidosis (loss of hydrocarbonates)

• Intestinal dyskinesia of hypokinetic type are manifestated by reduction of guts peristaltics. That results in appearance of constipations. On mechanisms of development it is pick out two kinds of constipations: spastic and atonic.

• Spastic constipations result from long tonic reduction of smooth muscles of guts (spasm) and may be caused by viscero-visceral reflexes, or action of toxic factors (for example, a poisoning by lead).

• Reason of development atonic constipations connected with reduction of contractive of function of smooth muscles guts:

• a poor feed, the low contents of cellulose in consumed foodstuffs

• excessive digestion peep in a stomach (for example, at gastric hypersecretion)

• age changes of receptor system of guts in old men, and also structural changes of an intestinal wall during adiposity

• decrease of tone vagal nerve• disturbances intraintestinal innervation, for example, during

Girshprungs disease - absence of ganglion cells Auerbachs plexus in sigmoideum and rectum

Intestinal dyskinesia of hypokinetic type lead to: development of intestinal autointoxication occurrence meteorism formation of feces stones in extreme cases intestinal obstruction may develop