Lecture 41 - Liver and Bile Acids Flashcards
what are the 3 main functions of the liver
- biotransformation
- storage
- synthesis
what are liver macrophages called
Kupffer cells
what are the additional functions of the liver
- bile production and secretion
- metabolism of protein, lipids, and carbs
- storage of glycogen, triglycerides, iron, copper, vitamins
- detoxification
- conversion of ammonia
- immune filter
- clotting factor production
T/F: the liver has a dual blood supply
TRUE
where does the liver receive blood from
- portal v. (75%)
- hepatic a. (25%)
describe the structure of the liver lobes
- hexagonal shape
- hepatocytes form cords radiating from central vein
- sinusoids lined with Kupffer cells
what composes the portal triad
- hepatic venule
- bile duct
- hepatic arteriole
what is the gall bladder
organ that stores bile
gallbladder contraction is stimulated by
CCK
T/F: horses don’t have gallbladders
TRUE
what is the limiting plate
ring of hepatocytes abutting the portal
Describe a classic hepatic lobule
based on blood flow
central vein and portal tracts at periphery
Describe portal lobules
based on bile flow; opposite to blood flow
organized as “triangle” with Portal tract at center
describe the route of bile through a portal lobule
- bile canaliculi
- canals
- bile ductules
- interlobular bile ducts
- intrahepatic ducts
- right/left ducts
- common hepatic duct
- common bile duct
- duodenum
what zones can the liver be divided into (name innermost to outermost)
- periportal (oxygenated blood)
- midzonal
- centrilobular (deoxygenated central v.)
hepatocytes in the periportal zone do what
- Cholesterol synthesis
- Fatty acid oxidation
- bile acid production
hepatocytes in the centrilobular zone do what
- glycolysis
- lipogenesis
- xenobiotic transformation
acinus
triangle-shaped unit containing a small portal tract (1) at the center and terminal hepatic venules (3) at the periphery
what amino acid is essential to cats
taurine
create a flowchart of the conversion of cholesterol to bile acid
cholesterol –[7a-hydroxylase]–> cholic acid –[taurine/glycine]–> taurocholic acid
T/F: bile acids are synthesized by Kuppfer cells
FALSE - hepatocytes
bile is an excretory route for what
fat-soluble metabolic waste (bilirubin, cholesterol, drugs, etc.)
T/F: the rate-limiting step of bile acid synthesis is 7a hydroxylation
TRUE
what drives bile acid transporation? what locations do they start and end in?
Bile Salt Export Pump (BSEP)
hepatocyte –> canalicular bile