Lesson 22 Pancreatic and Biliary Secretion 2024/25 PDF

Lesson 22 Pancreatic secretion and biliary system 3° Medicine Professor: Vittoria Carrabs PhD Academic year: 2024/25  1. Pancreatic secretion The pancreas plays a crucial role in digestion by producing both exocrine and endocrine secretions. 1. Exo...

Lesson 22 Pancreatic secretion and biliary system 3° Medicine Professor: Vittoria Carrabs PhD Academic year: 2024/25  1. Pancreatic secretion The pancreas plays a crucial role in digestion by producing both exocrine and endocrine secretions. 1. Exocrine Secretion: digestive enzymes, including amylase (for carbohydrate digestion), lipase (for fat digestion), and proteases (like trypsin and chymotrypsin, for protein digestion). It also secretes bicarbonate-rich fluid, which neutralizes stomach acid in the small intestine, providing an optimal environment for enzyme activity. 2. Endocrine Secretion: Specialized cells in the Islets of Langerhans (−cells) release hormones into the bloodstream, primarily insulin (which lowers blood glucose) and glucagon (which raises blood glucose). Other hormones like somatostatinand pancreatic polypeptide also play regulatory roles. Together, these secretions ensure proper digestion and regulate blood sugar levels.  1. Pancreatic secretion If pancreatic secretion is under 10% of the basal levels: PANCREATIC FAILURE Nutrients malabsorption Steatorrhea Faecal loss of proteins Due to acute pancreatitis, cystic fibrosis, pancreas cancer TREATMENT: Pancreatic enzymes TRIPSIN AMYLASE LIPASE PANCREATIN (preparation mixture of enzymes) Gastric antisecretion drugs or antiacids Anti-H2 or Antiacids *To avoid enzyme inactivation. 2. DRUGS AFFECTING THE BILIARY SYSTEM Biliary secretions produced by: Liver, stored in gallbladder Components: Bile salts: Emulsify fats for digestion Bilirubin: Waste product from red blood cells Cholesterol & phospholipids: Stabilize fat micelles Electrolytes & water: Maintain fluidity Functions: Fat emulsification & absorption (essential for vitamins A, D, E, K) Elimination of cholesterol and bilirubin Regulation: Cholecystokinin (CCK): Triggers bile release after fat intake Secretin: Stimulates bile rich in bicarbonate for acid neutralization 2. DRUGS AFFECTING THE BILIARY SYSTEM The commonest pathological condition of the biliary tract is CHOLESTEROL CHOLELITHIASIS: cholesterol is a natural component of bile, helping in fat digestion. However, when it becomes too concentrated, it can precipitate and form GALLSTONES. Cholelithiasis Causes: Excess Cholesterol in bile (supersaturation). Impaired Gallbladder Emptying (bile stasis). Reduced Bile Salts or phospholipids, which normally dissolve cholesterol. Risk Factors: Obesity, rapid weight loss, pregnancy, high-fat diet, and genetic predisposition 2. DRUGS AFFECTING THE BILIARY SYSTEM Types of Gallstones: Cholesterol stones: Most common, usually yellow-green. Pigment stones: Made of bilirubin, more common in chronic liver disease or infections. TREATMENT OF COLELITHIASIS: SURGERY is generally the preferred option (gallbladder removal) ORALLY ACTIVE DRUGS: dissolve cholesterol gallstones. URSODEOXYCHOLIC ACID, a minor constituent of human bile 2. DRUGS AFFECTING THE BILIARY SYSTEM TREATMENT BILIARY COLIC PAIN NSAIDs, MORPHINE Anti-inflammatory/analgesic drugs and analgesic BILIARY COLIC PAIN Produced by the passage of gallstones through the bile duct, can be very intense, and immediate relief may be required. 2. DRUGS AFFECTING THE BILIARY SYSTEM TREATMENT BILIARY COLIC PAIN BUPRENORPHINE (Opioid): Alternative to morphine MEPIRIDINE: (Opioid) Similar effects (also relaxes uretral muscles) ATROPINE (Muscarinic antagonist) To relieve biliary spasm May be used in conjunction with morphine GLYCERYL TRINITRATE To relieve biliary spasm. Can produce a marked fall of intrabiliary pressure