Liver: anatomy & functions Pavle Peić Tukuljac Mentor: A. Žmegač Horvat Anatomy • Largest gland in the body (1.5 Kg) • Under the diaphragm, within the rib cage in the upper right quadrant of the abdomen Anatomy •4 Lobes Major: left and right Minor: caudate and quadrate •Ducts Common hepatic Cystic From gallbladder Common bile Choledochus Joins pancreatic duct at hepatopancreatic ampulla GALLBLADDER ANATOMY GALLBLADDER ANATOMY • Thin-walled green muscular sac • On the inferior surface of the liver • Stores bile that is not immediately needed for digestion • When the muscular wall of the gallbladder contracts bile is expelled into the bile duct LIVER GALL BLADDER BILE • BILE – bile salts, bile pigments, cholesterol, neutral fats, phospholipids and electrolytes • Liver produces 0.5-1 l of bile daily • Bile salts emulsify fats LIVER GALL BLADDER LIVER ANATOMY • Liver lobules – hexagonal structures consisting of hepatocytes • Hepatocytes radiate outward from a central vein • At each of the six corners of a lobule is a portal triad • Liver sinusoids LIVER ANATOMY • Hepatocytes produce bile • Bile flows through canals called bile canaliculi to a bile duct • Bile ducts leave the liver via the common hepatic duct LIVER ANATOMY 20 % 80 % Functions • Metabolic Synthesis Breakdown Other functions – storage of vitamin A,D,B12,F… • Excretion of waste products from bloodstream into bile • Vascular – storage of blood Synthesis • Protein metabolism Synthesis of amino acids • Carbohydrate metabolism Gluconeogenesis Glycogenolysis Glycogenesis • Lipid metabolism Cholesterol synthesis Lipogenesis • Production of coagulation factors I, II, V, VII, IX, X and XI, and protein C, protein S and antithrombin • Main site of red blood cell production • Produces insulin-like growth factor 1 (IGF-1), a polypeptide protein – anabolic effects • Production of trombopoetin Breakdown • Breaks down insulin and other hormones • Breaks down hemoglobin • Breaks down or modifies toxic substances (methylation) → sometimes results in toxication • Converts ammonia to urea Other functions • Produces albumin, the major osmolar component of blood serum • Synthesizes angiotensinogen, the hormone responsible for raising blood pressure when activated by renin (enzyme released when the kidney senses low blood pressure) References • http://en.wikipedia.org/wiki/Liver • http://www.youtube.com/watch?v=J0AjkKRxb WM&feature=related • http://www.mamashealth.com/organs/liver.as p • www.medterms.com • http://www.youtube.com/watch?v=bx6kj6xLC Zw