Liver Anatomy and Physiology Lecture Notes PDF

Liver Anatomy and Physiology Chapter 16 Lec 11 Liver Anatomy • Located in the upper right quadrant of the abdomen • Largest gland in body • Located behind the ribs • 4 lobes – Right (largest), quadrate, caudate and the left – Made up of thousands of lobules around the central vein ‫تتكون من آالف...

Liver Anatomy and Physiology Chapter 16 Lec 11 Liver Anatomy • Located in the upper right quadrant of the abdomen • Largest gland in body • Located behind the ribs • 4 lobes – Right (largest), quadrate, caudate and the left – Made up of thousands of lobules around the central vein ‫تتكون من آالف الفصيصات حول الوريد املركزي‬ Liver Introduction • Chemical factory: manufactures, stores, and excretes a large number of substances involved in metabolism • Regulates glucose, protein, and fat metabolism • Removes waste products from blood • Ability to regenerate itself Liver Functions Liver function test • >70% of hepatic cells damaged before LFT’s become abnormal • Only 10-20% functioning liver required to sustain life Liver Functions • • • • • Metabolism of macronutrients Storage/activation of vitamins/mineral/enzymes Converts Ammonia to urea Detoxifies drugs & alcohol Filter and blood chamber ‫تحويل األمونيا إلى اليوريا‬ ‫يزيل سموم املخدرات والكحول‬ ‫تصفية وغرفة الدم‬ • Over 500 known functions Liver Functions • Glucose Metabolism – Portal venous blood supply Liver Glucose converted to Glycogen stored in Hepatocytes – Glycogen converted back into glucose as needed – Gluconeogenesis occurs in liver – Gluconeogenesis of aa = ammonia production (toxin), liver converts to urea and kidneys excrete Liver Functions • Protein Metabolism – Synthesizes almost all plasma proteins: – Albumin, alpha and beta globulins, blood clotting factors (prothrombin, fibrinogen), transport proteins (transferrin, ceruloplasmin), most plasma lipoproteins – Vitamin K required by liver for synthesis of prothrombin and other clotting factors Liver Functions • Fat Metabolism – Can be broken down for energy and production of ketone bodies – FA and their metabolic products also used to synthesize cholesterol, lecithin, lipoproteins, and other complex lipids – Lipids can accumulate in hepatocytes and cause fatty liver Vitamin and Mineral Storage ADEK • Fat soluble vitamins and B12 stored in liver • Iron, copper, zinc, and magnesium stored in liver • Hydroxylation of vitamin D to 25 OH D3 ‫مش الزم نحفظ وظايفهم لكن نحفظ إذا الكبد تأثر فهذول كمان يتأثروا‬ Liver Functions • Bile Secretions – Bile is composed of cholesterol, bile pigments, bile acids, phospholipids, bicarbonate and waste products – Emulsifying agent – 600 – 1000 mL of bile/d Liver Functions ‫الدورة الدموية املعوية الكبدية للصفراء‬ • Enterohepatic Circulation of Bile – 95% of bile salts are reabsorbed into the blood from the small intestine – Enter the portal blood and are returned to the liver – 2 to 3 X per meal ‫ في الكبد في الوجبة الوحدة‬circulation ‫مرتني إلى ثالثة يصير فيه‬ – 16 X per day Summary • The liver is the largest gland in the body that has multiple functions • The liver filters out toxins, • Many of those functions have nutrition consequences • As a dietitian, knowing the anatomy and physiology will play an important role in knowing what nutrition interventions are appropriate.