1. Duodenum, liver and Pancreas Prof. K. Sivapalan.

2. 2013Duodenum, Liver and Pancreas2 Duodenum Pancreas and liver develop from intestinal epithelium. The pancreatic duct and bile duct open into duodenum by common passage, Ampula of Vater, via sphinter of Oddi Duodenum secrets several hormons Mucus glands- HCO 3 production

3. 2013Duodenum, Liver and Pancreas3 Secretine It is the first hormone identified by Bayliss and Starling, [students] Secreted by S cells in duodenal mucosa. Stimulus- acid, products of protein digestion. Effects- –bicarbonate [watery alkaline] secretion from pancreas and biliary tract. –Inhibits acid secretion from stomach

4. 2013Duodenum, Liver and Pancreas4 Cholecystokinin [CCK-PZ]. Stimulus: –Fatty acids with more than 10 Carbon. –Digestive products of protein. Effects: –Contraction of gallbladder –Secretion of pancreatic juice rich in enzyme. –Inhibits gastric emptying. Positive feed back: effects increase stimuli

5. 2013Duodenum, Liver and Pancreas5 Pancreas Pancreatic juice: pH- 8, 1500 ml/day. Enzymes: –Trypsinogen, chymotrypsinogen, procarboxyl peptidases, lipase, amylase, ribonuclease, deoxyribonuclease, phospholipase, etc. Enterokinase converts Trypsinogen into active Trypsin which activates all other enzymes. In pancreas, a trypsin inhibitor prevents accidental activation of trypsin. If it fails acute pancreatitis can cause death by digestion of abdominal contents. Control- CCK, Secretin, Vagus[mild]

6. 2013Duodenum, Liver and Pancreas6 Liver Functions. Secretion –bile salts: synthesis, entero- hepatic circulation. –cholesterol and other lipids. –plasma proteins- clotting factors and albumin. Excretion of insoluble wastes by conjugation with glucuronic acid. –bile pigments [golden yellow] Inactivation of hormones Activation of hormones Metabolism: –Carbohydrate, protein, fat Detoxification –toxins and drugs –Intestinal toxins, amonia Storage: –Carbohydrate –Protein –Vitamins Protection- Kupffer cells

7. 2013Duodenum, Liver and Pancreas7 Bile 500 ml per day. Stored and concentrated in gallbladder. Continuous flow is prevented by Sphincter of Boyden, found before joining with pancreatic duct in ampula of Vater. both open through sphincter of Oddi. Gallstones: calcium bilirubinate or cholesterol. Can block bile duct and cause obstructive Jaundice