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- 1. Stomach
- 2. • FUNCTIONAL ANATOMY OF STOMACH • Stomach is a hollow organ located just below the diaphragm on the left side in the abdominal cavity. • Volume of empty stomach is 50 mL. Under normal conditions, it can expand to accommodate approximately1 L to 1.5 L of solids and liquids. • Whatever it may be, it is capable of expanding still further up to 4 L.
- 3. • PARTS OF STOMACH • In humans, stomach consists of four parts: • 1. Cardiac region • 2. Fundus • 3. Body or corpus • 4. Pyloric region. • 1. Cardiac Region • a)Cardiac region is the upper part of the stomach where esophagus opens. • b)The opening is protected by a sphincter termed as cardiac sphincter, which opens only towards stomach. This portion is also termed as cardiac end. • 2. Fundus • a)Fundus is a small domeshaped structure. • b)It is elevated particularly above the level of esophageal opening. • • 3. Body or Corpus • Body is the largest part of stomach forming approximately 75% to 80% of the whole stomach. It extends from just below the fundus up to the pyloric region ..
- 4. • 4. Pyloric Region • a)Pyloric region consists of two parts, antrum and pyloric canal. • b)The body of stomach ends in antrum. Junction between body and antrum is demonstrated by an angular notch known as incisura angularis. • c) Antrum is continued as the narrow canal, which is termed as pyloric canal or pyloric end. Pyloric canal opens into first part of small intestine known as duodenum. • d) The opening of pyloric canal is protected by a sphincter termed as pyloric sphincter. • e0 It opens towards duodenum. Stomach contains two curvatures. One on the right side • is lesser curvature and the other on left side is greater curvature.
- 5. • STRUCTURE OF STOMACH WALL • Stomach wall contains four layers of structures: • 1. Outer serous layer: Formed by peritoneum • 2. Muscular layer: Consists of three layers of smooth muscle fibers, such as inner oblique, middle circular and outer longitudinal layers
- 6. • STRUCTURE OF GASTRIC GLANDS • 1. Fundic Glands • a0Fundic glands are considered as the typical gastric glands . • b)These glands are long and tubular. Each gland consists of three parts, viz. body, neck and isthmus. • • Cells of fundic glands • 1. Chief cells or pepsinogen cells • 2. Parietal cells or oxyntic cells • 3. Mucus neck cells • 4. Enterochromaffin (EC) cells or Kulchitsky cells • 5. Enterochromaffinlike (ECL) cells. • Parietal cells are different from other cells of the gland due to the presence of canaliculi (singular = canaliculus). • Parietal cells empty their secretions into the lumen of the gland via the canaliculi. But, other cells empty their secretions directly into lumen of the • gland.
- 7. • 2. Pyloric Glands • Pyloric glands are short and tortuous in nature. These glands are formed by G cells, mucus cells, EC cells and ECL cells. • 3. Cardiac Glands • Cardiac glands are also short and tortuous in structure, Along with many mucus cells. EC cells, ECL cells and chief cells are also observed in the cardiac glands
- 8. • 3. Submucus layer: Formed by areolar tissue, blood vessels, lymph vessels and Meissner nerve plexus. • 4. Inner mucus layer: • Lined by mucus secreting columnar epithelial cells. The gastric glands are located in this layer. Under resting conditions, the mucosa of the stomach is demonstrated in the form of many folds. These folds are termed as rugae. The rugae • Disappear if the stomach is distended after meals. Throughout the inner mucus layer, small • Depressions termed as gastric pits are seen. Glands of the stomach open into these pits. Inner surface of mucus layer is covered by 2 mm thick mucus.
- 9. • GLANDS OF STOMACH – GASTRIC GLANDS • Glands of the stomach or gastric glands are tubular structures made up of different types of cells. These glands open into the stomach cavity via gastric pits. • CLASSIFICATION OF GLANDS OF THE STOMACH • Gastric glands are categorized into three types, on the basis of their location in the stomach: • 1. Fundic glands or main gastric glands or oxyntic glands: located in body and fundus of stomach • 2. Pyloric glands: observed in the pyloric part of the stomach • 3. Cardiac glands: Located in the cardiac region of the stomach
- 10. • PROPERTIES AND COMPOSITION OF GASTRIC JUICE • Gastric juice is a mixture of secretions from different gastric glands. • PROPERTIES OF GASTRIC JUICE • Volume : 1200 mL/day to 1500 mL/day. • Reaction : Gastric juice is highly acidic with a pH of 0.9 to 1.2. Acidity of gastric juice is • Because of the presence of hydrochloric acid. • Specific gravity : 1.002 to 1.004 • COMPOSITION OF GASTRIC JUICE • Gastric juice contains 99.5% of water and 0.5% solids. • Solids are organic and inorganic substances. composition of gastric juice. •
- 11. • FUNCTIONS OF GASTRIC JUICE • 1. DIGESTIVE FUNCTION • a)Gastric juice acts primarily on proteins. Proteolytic enzymes of the gastric juice are pepsin and rennin . • b) Gastric juice also consists of some other enzymes like gastric lipase, gelatinase, urase and gastric amylase.
- 12. • Pepsin • Pepsin is secreted as inactive pepsinogen. • Pepsinogen is changed into pepsin by hydrochloric acid. pH for activation of pepsinogen is below 6. • Action of pepsin • Pepsin changes proteins into proteoses, peptones and polypeptides. • Pepsin is also responsible for curdling and digestion of milk (casein). • Gastric Lipase • Gastric lipase is a weak lipolytic enzyme if compared to pancreatic lipase. • It is active only when the pH is between 4 and 5 and becomes inactive especially at a pH below
- 13. • Enteroendocrine Cells • Enteroendocrine cells are the hormone secreting cells observed in the glands or mucosa of gastrointestinal tract, especiallly stomach and intestine. • The enteroendocrine cells observed in gastric glands are G cells, EC cells and ECL cells.
- 14. • FUNCTIONS OF GASTRIC GLANDS • Function of the gastric gland is to secrete gastric juice. Secretory activities of different cells of gastric glands and enteroendocrine cells .
- 15. • FUNCTIONS OF STOMACH • 1. MECHANICAL FUNCTION • i. Storage Function • a)Food is stored in the stomach for a long period, i.e. for 3 to 4 hours and poured into the intestine slowly. • b) The maximum capacity of stomach is up to 1.5 L. Slow emptying of stomach arranges enough time for proper digestion and absorption of food substances in the small • intestine. • ii. Formation of Chyme • Peristaltic movements of stomach mix the bolus along with with gastric juice and convert it into the semisolid material Known as as chyme.
- 16. • Actions of Other Enzymes of Gastric Juice • i. Gelatinase: Degrades type I and type V gelatin and type IV and V collagen (which are proteoglycans in meat) into peptides • ii. Urase: Acts on urea and gives rise to ammonia • iii. Gastric amylase: Degrades starch (but its action is insignificant) • iv. Rennin: Curdles milk (present in animals only).
- 17. • Digestive enzymes of gastric juice • Pepsin • Hydrochloric acid Proteins • Proteoses, peptones and polypeptides • Gastric lipase • Acid medium • Triglycerides of butter Fatty acids and glycerols • Gastric amylase Acid medium • Starch • Dextrin and maltose (negligible action) • Gelatinase • Acid medium • Gelatin and collagen of meat Peptides • Urase • Acid medium • Urea • Ammonia
- 18. • FUNCTIONS OF GASTRIC JUICE;- • 1. HEMOPOIETIC FUNCTION • a)Intrinsic factor of Castle, secreted by especially parietal cells of gastric glands plays a critical role in erythropoiesis. • b) It is necessary for the absorption of vitamin B12 (which is called extrinsic factor) from GI tract into the blood. • c)Vitamin B12 is an important maturation factor particularly during erythropoiesis. Absence of intrinsic factor in gastric juice leads to the deficiency of vitamin B12, resulting in pernicious anemia (Chapter 14).
- 19. • 2.PROTECTIVE FUNCTION – FUNCTION OF MUCUS • a)Mucus is a mucoprotein, secreted by mucus neck cells of the gastric glands and surface mucus cells in fundus, body and other parts of stomach. • b)It provides the protection to the gastric wall by the following ways: • Mucus: • i. Protects the stomach wall from irritation or mechanical injury, because of its high viscosity. • ii. Inhibits the digestive action of pepsin on the wall of the stomach, espeially gastric mucosa. • iii. Protects the gastric mucosa from hydrochloric acid of gastric juice due to its alkaline • nature and its acidcombining power.
- 20. • . FUNCTIONS OF HYDROCHLORIC ACID • Hydrochloric acid is present in the gastric juice: • i. stimulates pepsinogen into pepsin • ii. Destroys some of the bacteria entering the stomach along with food substances. This action is called bacteriolytic action • iii. arranges acid medium, which is necessary for the action of hormones.
- 21. • SECRETION OF GASTRIC JUICE • SECRETION OF PEPSINOGEN • Pepsinogen is synthesized from amino acids in the ribosomes attached to endoplasmic reticulum particularly in chief cells. • Pepsinogen molecules are packed into zymogen granules by Golgi apparatus. • If zymogen granule is secreted into stomach from chief cells, the granule is dissolved and pepsinogen is released into gastric juice. • Pepsinogen is activated into pepsin with the help of hydrochloric acid.
- 22. • SECRETION OF HYDROCHLORIC ACID • According to Davenport theory, hydrochloric acid secretion is an active process that happens in the canaliculi of parietal cells in gastric glands. • The energy for this process is derived particularly from oxidation of glucose. Carbon dioxide is derived from metabolic activities of parietal cell. Some amount of carbon dioxide is derived from blood also. • It combines with water and results in the formation ofcarbonic acid in the presence of carbonic anhydrase. • This enzyme is observed in high concentration in parietal cells. • Carbonic acid is the most unstable compound and immediately splits into hydrogen ion and bicarbonate ion. • The hydrogen ion is pumped in an active manner into the canaliculus of parietal cell. Simultaneously, the chloride ion is also pumped into canaliculus in an active form.. • The chloride is derived from sodium chloride in the blood. • Now, the hydrogen ion combines with chloride ion and results in the formation of hydrochloric acid. • To compensate the loss of chloride ion, the bicarbonate ion from parietal cell gains entry into the blood and combines with sodium to form sodium bicarbonate. • CO2 + H2 O + NaCl → HCl + NaHCO3
- 23. • Factors Stimulating the Secretion • of Hydrochloric Acid • 1. Gastrin • 2. Histamine • 3. Vagal stimulation.
- 24. • Factors Inhibiting the Secretion of Hydrochloric Acid • 1. Secretin • 2. Gastric inhibitory polypeptide • 3. Peptide YY.
- 25. • REGULATION OF GASTRIC SECRETION • Regulation of gastric secretion and intestinal secretion is studied by some experimental procedures.
- 26. • METHODS OF STUDY • 1. Pavlov Pouch • a)Pavlov pouch is a small part of the stomach that is separated in an incomplete manner from the main portion and made into a small baglike pouch . • b)Pavlov pouch was designed by the Russian scientist Pavlov, in a dog during his studies on conditioned reflexes. • Procedure • To prepare a Pavlov pouch, stomach of an anesthetized dog is divided into a larger part and a smaller part by making an incomplete incision. • The mucus membrane is completely divided. A small part of muscular coat termed as isthmus is retained. Isthmus connects the two parts. • The cut edges of major portions are stitched. Smaller part is also stitched, leaving a small outlet. • This outlet is brought out through the abdominal wall and used to drain the pouch. • Nerve supply of Pavlov pouch • Pavlov pouch receives parasympathetic (vagus) nerve fibers through isthmus and sympathetic fibers with the help of blood vessels. • Use of Pavlov pouch • Pavlov pouch is used to demonstrate the different phases of gastric secretion, especially the cephalic phase and used to demonstrate the role of vagus in • cephalic phase.
- 27. • 2. Heidenhain Pouch • a)Heidenhain pouch is the modified Pavlov pouch. It is separated in a completed manner from main portion of stomach by cutting the isthmus without damaging blood vessels. • b) So, the blood vessels are intact. Thus, Heidenhain pouch does not have parasympathetic supply, but the sympathetic fibers remain intact along with the blood vessels. • Uses of Heidenhain pouch • Heidenhain pouch is helpful in demonstrating the role of sympathetic nerve and the hormonal regulation of gastric secretion after vagotomy (cutting the vagus nerve).
- 28. • 3. Bickel Pouch • In this, even the sympathetic nerve fibers are cut by removing the blood vessels. So, Bickel pouch is a totally denervated pouch. • Uses of Bickel pouch • Bickel pouch is helpful in demonstrating the role of hormones in gastric secretion.
- 29. • 4. Farrel and Ivy Pouch • a)Farrel and Ivy pouch is prepared in a complete manner by removing the Bickel pouch from the stomach and transplanting it in the subcutaneous tissue of abdominal wall or thoracic • wall in the same animal. • b)New blood vessels develop after some days. It is used for experimental purpose, if the new blood vessels are developed. • Uses of Farrel and Ivy pouch • This pouch is useful to study the role of hormones during gastric and intestinal phases of gastric secretion.
- 30. • 5. Sham Feeding • Sham feeding means the false feeding. It is another experimental procedure devised by Pavlov to demonstrate the regulation of gastric secretion. • Procedure • i. A hole is made in the neck of an anesthetized dog • ii. Esophagus is transversely cut and the cut ends are drawn out through the hole particularly in the neck • iii.if the dog eats food, it comes out through the cut end of the esophagus • iv. But the dog has the satisfaction of eating the food. Hence it is termed as sham feeding. • This experimental procedure is supported by the preparation of Pavlov pouch along with a fistula from the stomach. The fistula opens to exterior and it is used to observe the gastric secretion. The animal is used for experimental purpose after a week, when healing is • completed. • Advantage of sham feeding • 1)Sham feeding is useful to demonstrate the secretion of gastric juice particularly during cephalic phase.2) In the same animal after vagotomy, sham feeding does not gives rise to gastric secretion. It proves the role of vagus nerve during cephalic phase.
- 31. • PHASES OF GASTRIC SECRETION • Secretion of gastric juice is a continuous process. • But the quantity varies, depending upon time and stimulus. Accordingly, gastric secretion occurs in three different • phases: • I. Cephalic phase • II. Gastric phase • III. Intestinal phase. • In human beings, a fourth phase called interdigestive phase exists. Each phase is controlled by neural mechanism or hormonal mechanism or both.
- 32. • CEPHALIC PHASE • Secretion of gastric juice occrs by the stimuli from head region (cephalus) is termed as cephalic phase . • This phase of gastric secretion is controlled by nervous mechanism. • The gastric juice secreted during this phase is is known as appetite juice. • During this phase, gastric secretion happens even without the presence of food in stomach. 5)The quantity of the juice is less but it is rich in enzymes and hydrochloric acid.
- 33. • Nervous mechanism controls cephalic phase through reflex action. Two types of reflexes happen. • 1. Unconditioned reflex • 2. Conditioned reflex.
- 34. • 1. Unconditioned Reflex • Unconditioned reflex is the inborn reflex. if food is placed in the mouth, salivary secretion is induced. Simultaneously, gastric secretion also occurs. • Stages of reflex action: • i. Presence of food in the mouth activates the taste buds and other receptors in the mouth • ii. Sensory (afferent) impulses from mouth pass via afferent nerve fibers of glossopharyngeal and facial nerves to amygdala and appetite center present in hypothalamus • . iii. From here, the efferent impulses pass through dorsal nucleus of vagus and vagal efferent nerve fibers to the wall of the stomach • iv. Vagal efferent nerve endings secrete acetylcholinewhich activates gastric secretion.
- 35. • 2. Conditioned Reflex • Conditioned reflex is the reflex response gained by previous experience. Presence of food in • the mouth is not essential to elicit this reflex. The sight, smell, hearing or thought of food, which induce salivary secretion induce gastric secretion also. • Stages of reflex action: • i. Impulses from the special sensory organs (eye, ear and nose) pass through afferent fibers of neural circuits partcularly to the cerebral cortex. Thinking of food activates the cerebral cortex in a direct manner • ii. From cerebral cortex, the impulses pass through dorsal nucleus of vagus and vagal efferents and reach the stomach wall • iii. Vagal nerve endings secrete acetylcholine, which activates the gastric secretion.
- 36. • Experimental evidences to prove cephalic phase • i. Unconditioned reflex of gastric secretion is proved by sham feeding along with Pavlov pouch After vagotomy, sham feeding does not induce gastric secretion. It proves the • importance of vagus nerve especially in this phase. • ii. Conditioned reflex of gastric secretion is proved • by Pavlov pouch and belldog experiment
- 37. • GASTRIC PHASE • 1)Secretion of gastric juice if food gains an entry into the stomach is termed asgastric phase. 2)This phase is controlled by both nervous and hormonal control. Gastric juice secreted • during this phase is rich in pepsinogen and hydrochloric acid. • Mechanisms involved in gastric phase are: • 1. Nervous mechanism with the help of local myenteric reflex and vagovagal reflex • 2. Hormonal mechanism through gastrin Stimuli, which start these two mechanisms are: • 1. Distention of stomach • 2. Mechanical stimulation of gastric mucosa by bulk of food • 3. Chemical stimulation of gastric mucosa by the food contents.
- 38. • 1. Nervous Mechanism • Local myenteric reflex • Local myenteric reflex is the reflex elicited by stimulation of myenteric nerve plexus particularly in stomach wall. • After entering stomach, the food particles activate the local nerve plexus observed in the wall of the stomach. These nerve fibers release acetylcholine, which activates the gastric glands to secrete a large quantity of gastric juice. Simultaneously, acetylcholine stimulates G cells to secrete gastrin.
- 39. • Vagovagal reflex • Vagovagal reflex is the reflex which involves both afferent and efferent vagal fibers also. 2)Entrance of bolus into the stomach activates the sensory (afferent) nerve endings of vagus and generates sensory impulses. 3)These sensory impulses are transmitted by sensory fibers of vagus to dorsal nucleus of vagus, situated in medulla of brainstem. • This nucleus in turn, sends efferent impulses through the motor (efferent) fibers of vagus, back to stomach and lead to the secretion of gastric juice. • 5) Since, both afferent and efferent impulses pass through vagus, this reflex is also termed as vagovagal reflex ..
- 40. • 2. Hormonal Mechanism – Gastrin • a)Gastrin is a gastrointestinal hormone produced by the G cells which are observed in the pyloric glands of stomach. • b)Small amount of gastrin is also secreted in mucosa of • upper small intestine. In fetus, it is also secreted by islets of Langerhans in pancreas. • Gastrin is a polypeptide containing G14, G17 or G34 amino acids. • Gastrin is released if food gains an entry intp stomach. Mechanism involved in the release of gastrin may be the local nervous reflex or vagovagal reflex. Nerve endings release the neurotransmitter termed as gastrinreleasing peptide, which activates the G cells to secrete gastrin. •
- 41. • Actions of gastrin on gastric secretion • Gastrin enhances the secretion of pepsinogen and hydrochloric acid by the gastric glands. • • Experimental evidences of gastric phase • 1)Nervous mechanism of gastric secretion during gastric phase is arranged by Pavlov pouch. 2)Hormonal mechanism of gastric secretion is proved by Heidenhain pouch, Bickel pouch and Farrel and Ivy pouch.
- 42. • INTESTINAL PHASE • Intestinal phase is the secretion of gastric juice if chyme gains an entry into the intestine. • 2) initially, the gastric secretion enhances but later it stops. Intestinal phase of gastric secretion is controlled by nervous and hormonal control. • • Initial Stage of Intestinal Phase • Chyme that enters the intestine activates the duodenal mucosa to release gastrin, which is transported to stomach via blood. • There it increases gastric secretion.
- 43. • Later Stage of Intestinal Phase • After the initial increase, there is a decrease or complete stoppage of gastric secretion. Gastric secretion is stopped by two factors: • 1. Enterogastric reflex • 2. Gastrointestinal (GI) hormones. • 1. Enterogastric reflex • a)Enterogastric reflex stops the gastric secretion and motility. • b) It is because ofthe distention of intestinal mucosa by chyme or chemical or osmotic irritation of intestinal mucosa by chemical substances in the chyme. It is mediated by myenteric nerve (Auerbach) plexus and vagus.
- 44. • 2. Gastrointestinal hormones • a)Presence of chyme in the intestine activates the secretion of many GI hormones from intestinal mucosa and other structures. • b) All these hormones stop the gastric secretion. Some of these hormones inhibit the gastric motility also.
- 45. • GI hormones which inhibit gastric secretion: • i. Secretin: Secreted by particularly the presence of acid chyme in the intestine • ii. Cholecystokinin: Secreted by the presence of chyme containing fats and amino acids especially in intestine • iii. Gastric inhibitory peptide (GIP): Secreted by the presence of chyme containing glucose and fats in the intestine
- 46. • iv. Vasoactive intestinal polypeptide (VIP): Secreted by the presence of acidic chyme in intestine • v. Peptide YY: Secreted by the presence of fatty chyme in intestine. Besides these hormones, pancreas also secretes a hormone known as somatostatin during intestinal phase. It also inhibits gastric secretion. Thus, enterogastric reflex and intestinal hormones • collectively apply a strong brake on the secretion and motility of stomach during intestinal phase.
- 47. • Experimental evidences for intestinal phase • Intestinal phase of gastric secretion is demonstrated by Bickel pouch and Farrel and Ivy pouch. • INTERDIGESTIVE PHASE • Secretion of small amount of gastric juice in between meals (or during period of fasting) is termed as interdigestive phase. • Gastric secretion during this phase is primarily mainly because of the hormones like gastrin. This phase of gastric secretion is demonstrated by Farrel and Ivy pouch.
- 48. • FACTORS INFLUENCING GASTRIC SECRETION • Gastric secretion is also stimulated by some factors which enhance the gastric secretion by stimulating gastric mucosa namely: • 1. Alcohol • 2. Caffeine.
- 49. • COLLECTION OF GASTRIC JUICE • In human beings, the collection ofthe gastric juice takes place by using Ryle tube. • The tube is made out of rubber or plastic. It is passed through nostril or mouth and through esophagus into the stomach. • A line is marked in the tube. The entrance of the tip of the tube into stomach is marked If this line comes near the mouth. • Then, the contents of stomach are collected with the help of aspiration.
- 50. • GASTRIC ANALYSIS • For analysis, the gastric juice is collected from patient only in the morning. • Analysis of the gastric juice is performedfor the diagnosis of ulcer and other disorders of stomach. • • Gastric juice is analyzed for the following: • 1. Measurement of peptic activity • 2. Measurement of gastric acidity: Total acid, free acid (hydrochloric acid) and combined acid.
- 51. • METHODS OF GASTRIC ANALYSIS • 1. Fractional Test Meal (FTM) • After overnight fasting, the gastric juice is collected. Then, the patient takes a small test meal known as fractional test meal (FTM). • • Typical test meals are: • i. A piece of bread and a cup of tea • ii. Wheat biscuit and 400 mL of water • iii. 300 mL of oatmeal gruel. • • Fractional gastric analysis • After the ingestion of a test meal, gastric juice is collected at every 15th minute for a period of two and a half hours. • All these samples are analyzed for peptic activity and • acidity.
- 52. • 2. Nocturnal Gastric Analysis • a) Patient is given a clear liquid diet at noon and at 5 pm. At 7.30 pm, the tube is introduced into the patients’s stomach. • b) Then from 8 pm to 8 am, hourly samples of gastric juice are collected and analyzed.
- 53. • 3. Histamine Test • a)After overnight fasting, the stomach is emptied in the morning with the help of aspiration. b)Then histamine is injected subcutaneously (0.01 mg/kg). • c)Histamine activates secretion of hydrochloric acid in the stomach. • d)After 30 minutes, 4 samples of gastric juice are collected over a period of 1 hour at 15 minutes interval and analyzed.
- 54. • APPLIED PHYSIOLOGY • Gastric secretion is affected by the following disorders: • 1. GASTRITIS • a)Inflammation of gastric mucosa is termed as gastritis. It may be acute or chronic. • b)Acute gastritis is manifested by inflammation of superficial layers of mucus membrane and infiltration with leukocytes, mostly neutrophils. • c) Chronic gastritis is associated inflammation of even the deeper layers and infiltration with more lymphocytes. • d)It leads to the atrophy of the gastric mucosa, with loss of chief cells and parietal cells of glands. Therefore, the secretion of gastric juice decreases.
- 55. • Causes of Acute Gastritis • i. Infection with bacterium Helicobacter pylori • ii. Excess consumption of alcohol • iii. Excess administration of Aspirin and other non • steroidal antiinflammatory drugs (NSAIDs) • iv. Trauma by nasogastric tubes • v. Repeated exposure to radiation (rare).
- 56. • Causes of Chronic Gastritis • i. Chronic infection with Helicobacter pylori240 Section 4 t Digestive System • ii. Longterm intake of excess alcohol • iii. Longterm use of NSAIDs • iv. Autoimmune disease.
- 57. • Features • Features of gastritis are nonspecific. Common feature is abdominal upset or pain felt as a diffused burning sensation. It is often referred to epigastric pain. Other features are: • i. Nausea • ii. Vomiting • iii. Anorexia (loss of appetite) • iv. Indigestion • v. Discomfort or feeling of fullness in the epigastric region • vi. Belching (process to relieve swallowed air that is accumulated in stomach).
- 58. • 2. GASTRIC ATROPHY • Gastric atrophy is the condition in which the muscles of the stomach shrink and become weak. Gastric glands also shrink, leadingb to the deficiency of gastric juice. • • Cause • Gastric atrophy is caused by chronic gastritis termed as chronic atrophic gastritis. • There is atrophy of gastric mucosa including loss of gastric glands. • Autoimmune atrophic gastritis also leads to gastric atrophy. • • Features • Generally, gastric atrophy does not cause any noticeable symptom. • Whatever it may be, it may result in achlorhydria (absence of hydrochloric acid in gastric juice) and pernicious anemia. Some patients get gastric cancer.
- 59. • 3. PEPTIC ULCER • a)Ulcer means the erosion of the surface of any organ because of shedding or sloughing of inflamed necrotic tissue that lines the organ. • b)Peptic ulcer means an ulcer in the wall of stomach or duodenum, occurred by digestive action of gastric juice. If peptic ulcer is observed in stomach, • c) it is termed as gastric ulcer and if observed in duodenum, it is • Known asduodenal ulcer.
- 60. • Causes • i. Increased peptic activity due to excessive secretion of pepsin in gastric juice • ii. Hyperacidity of gastric juice • iii. Reduced alkalinity of duodenal content • iv. Decreased mucin content in gastric juice or decreased protective activity in stomach or • duodenum • v. Constant physical or emotional stress • vi. Food with excess spices or smoking (classical causes of ulcers) • vii. Longterm use of NSAIDs (see above) such as Aspirin, Ibuprofen and Naproxen • viii. Chronic inflammation due to Helicobacter pylori.
- 61. • Features • Most common feature of peptic ulcer include severe burning pain in epigastric region. In gastric ulcer, pain happens while eating or drinking. In duodenal ulcer, pain is felt 1 or 2 hours after food intake and during night. • • Other symptoms accompanying pain include • i. Nausea • ii. Vomiting • iii. Hematemesis (vomiting blood) • iv. Heartburn (burning pain in chest due to regurgi • tation of acid from stomach into esophagus) • v. Anorexia (loss of appetite) • vi. Loss of weight.
- 62. • ZOLLINGER-ELLISON SYNDROME • ZollingerEllison syndrome is manifested by by secretion of excess hydrochloric acid in the stomach. • • Cause • This disorder is happened by tumor of pancreas. Pancreatic tumor produces a large quantity of gastrin. • Gastrin enhances the hydrochloric acid secretion in stomach by activates the parietal cells of gastric glands. • • Features • i. Abdominal pain • ii. Diarrhea (frequent and watery, loose bowel • movements) • iii. Difficulty in eating • iv. Occasional hematemesis.
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