Recommandé
Contenu connexe
Similaire à PANCREAS.ppt DIGESTIVE SYSTEM PHYSIOLOGY
Similaire à PANCREAS.ppt DIGESTIVE SYSTEM PHYSIOLOGY (20)
Plus de Vigneswaran31
Dernier
Dernier (20)
PANCREAS.ppt DIGESTIVE SYSTEM PHYSIOLOGY
- 1. PANCREAS Vigneswaran Ganesan M.sc., Senior Lecturer Department of Biochemistry
- 3. PANCREAS dual organ having two functions FUNCTIONAL ANATOMY OF EXOCRINE PART OF PANCREAS Structure resembles salivary gland Made up of acini or alveoli Acinus – has a single layer of acinar cells with a lumen in the center. The acinar cells contain zymogen granules, which possess digestive enzymes. FUNCTIONS Endocrine function - Production of hormones Exocrine function - Secretion of digestive juice (Pancreatic juice)
- 5. Small duct arises from the lumen of the alveolus Some of these ducts from neighboring alveoli unite to form intralobular duct. All intralobular duct. joins common bile duct to form ampulla of vater. Which opens in the duodenum main pancreatic duct WIRSUNG DUCT unite to form • Accessory duct (duct of Santorini) Exists in some persons Also opens into duodenum, proximal to the opening of ampulla of vater.
- 7. Pancreas is supplied by both sympathetic and parasympathetic fibers. Sympathetic fibers are supplied through splanchnic nerve Parasympathetic fibers are supplied through vagus nerve.
- 8. Volume : 500 to 800 mL/day Reaction : Highly alkaline with pH of 8 to 8.3 Specific gravity : 1.010 to 1.018
- 10. It plays an important role: in digestion of lipids proteins and carbohydrates, in metabolism since it produces insulin and other hormones. in neutralizing the pH to become suitable for the action of the pancreatic digestive enzymes.
- 11. DIGESTIVE FUNCTIONS Proteolytic enzymes – secreted as inactive precursors trypsinoge n trypsin enterokinas e chymotrypsinogen procarboxypeptidase chymotrypsin carboxypeptidas e Single polypeptide Mw 25000 229 aas polypeptide Mw 25700 246 aas
- 14. CA- CARBONIC ANHYDRASE H2CO3 - CARBONIC ACID CO2 diffuses to the ductule cells from blood CO2 combines with H2O in presence of CA to form H2CO3 H2CO3 dissociate into HCO3 - and H+ . The HCO3 - is actively transported into the lumen.
- 15. The H+ formed are exchanged for Na+ ions by active transport through blood , which will diffuse or actively be transported to the lumen
- 16. The movement of HCO3 - and Na+ ions to the lumen causes an osmotic gradient causes water to move from blood to ductule cells of the pancreas producing eventually the HCO3 - solution
- 17. Secretion of pancreatic juice is stimulated by: Secretin: ◦ Occurs in response to duodenal pH < 4.5. ◦ Stimulates production of HC03 - by pancreas. ◦ Stimulates the liver to secrete HC03 - into the bile. CCK: ◦ Occurs in response to fat and protein content of chyme in duodenum. ◦ Stimulates the production of pancreatic enzymes. ◦ Enhances secretin. Relaxation of the sphincter of Oddi.
- 19. Pancreatitis (inflammation in pancreatic acini) Acute and chronic- Types Acute- develops rapidly ,Chronic- progressive inflammatory disease with severe structural changes and loss of functions Causes of pancreatitis Long-time consumption of low alcohol. Congenital abnormalities of pancreatic duct. Malnutrition (poor nutrition; mal = bad). Heavy alcohol intake. Gallstones Features of pancreatitis Absence of pancreatic enzymes. Steatorrhea. Severe abdominal pain. Nausea and vomiting. Loss of appetite and weight. Fever. Shock.
- 20. Steatorrhea is the formation of bulky, foul smelling, frothy and clay colored stools with large quantity of undigested fat because of impaired digestion and absorption of fat. Causes of Steatorrhea 1. Lack of pancreatic lipase. 2. Liver disease affecting secretion of bile. 3. Atrophy of intestinal villi.
- 22. a. Alkaline PH b. Enterokinase c. Bile salts d. Chloride ion
- 23. a. Alkaline PH b. Enterokinase c. Bile salts d. Chloride ion
- 26. a. Gastrin b. Bile salts c. Enterokinase d. Chloride ions
- 27. a. Gastrin b. Bile salts c. Enterokinase d. Chloride ions
- 28. a. Its pH is about 8 b. Has high HCO₃⁻ content c. It’s secretion is primarily under neural control d. Contains digestive enzymes
- 29. a. Its pH is about 8 b. Has high HCO₃⁻ content c. It’s secretion is primarily under neural control d. Contains digestive enzymes
- 30. a. Bile salts b. Trypsin c. Cl ⁻ ions d. Enterokinase
- 31. a. Bile salts b. Trypsin c. Cl ⁻ ions d. Enterokinase
- 32. a. 0.6 liter b. 1.5 liter c. 3 liter d. 2.5 liter
- 33. a. 0.6 liter b. 1.5 liter c. 3 liter d. 2.5 liter
- 34. a. Sympathetic stimulation inhibits pancreatic HCO₃⁻ secretion b. The cephalic phase accounts for about 20 % of secretion after meal c. Pancreatic HCO3 depresses further release of secretin d. Contains enzymes which digest polysaccharides to
- 35. a. Sympathetic stimulation inhibits pancreatic HCO₃⁻ secretion b. The cephalic phase accounts for about 20 % of secretion after meal c. Pancreatic HCO3 depresses further release of secretin d. Contains enzymes which digest polysaccharides to
- 36. a. Somatostatin b. Glucagon c. Acid in the duodenum d. Sympathetic stimulation.
- 37. a. Somatostatin b. Glucagon c. Acid in the duodenum d. Sympathetic stimulation.
- 38. a. Maldigestion b. Malabsorption c. Dehydration d. Alkalosis
- 39. a. Maldigestion b. Malabsorption c. Dehydration d. Alkalosis