Liver Flashcards
What does the hepatic portal vein do?
Collects blood from capillaries stomach, spleen, pancreas, and intestine and empties into the liver
What is bile made up of?
Where does it go?
- Bile is made up of bile salts and the trash the liver wants to get rid of
- Bile salts help break down lipids in the intestine
- Bile gets stored in the gallbladder until “mealtime” when it is released into the intestine.
How much of the body’s lymph is made in the liver?
about half.
Lymph from the liver has more proteins than the rest of the body because there are large pores in the epithelium
Bile canaliculus
Collects bile secreted by the hepatocytes. Merges with the bile duct
Carbohydrate metabolism of the liver
- Storage of large amounts of glycogen
- conversion of galactose and fructose to glucose
- gluconeogenesis
- formation of many chemical compounds from intermediate products of carbohydrate metabolism
Protein metabolism
- Deamination of amino acids
- formation of urea for removal of ammonia from the body fluids
- formation of plasma proteins
- interconversion of the various amino acids and synthesis of other compounds from amino acids
Fat metabolism
- Oxidation of fatty acids to supply energy for other body functins
- Synthesis of large quantities of cholesterol, phospholipids, and most lipoproteins
- synthesis of fat from proteins and carbohydrates
Other metabolic functions of the liver
- Storage for vitamins A,D, and B12
- sores Iron as Ferritin
- forms the blood substances used in coagulation
- removes or excretes drugs, hormones, and other substances
What makes the liver so important for drug metabolism?
The liver is the only way to get rid of large, fat soluble molecules.
As the blood flows through the liver, it has more/less oxygen in it?
less
As the blood flows through the liver it has more/less extrahepatic hormones in it?
less
As the blood flows through the liver, it has more/less glycolysis enzymes in it?
more
As the blood flows through the liver, it has more/less glucose liberating enzymes
less
What does the hepatocyte do regarding glucose and protein?
- after a meal liver aggresively takes up glucose
- stores it as glycogen
- between meals break down glycogen and release it slowly
- Liver also builds protein
When protein intake is low, what are the first proteins to not be made?
albumin
What is the process of bile?
- Amino acids (glycine or taurine) conjugate bile acids to form bile salts
- some goes to gallbladder for storage until next meal
- some goes to duodenum and jejunum to emulsify fats
- 65-85% of bile is reabsorbed through the intestinal lumen and binds to protein in circulation and transported to liver
- in liver it rejoins bile pool
What is the process of red blood cell destruction?
- Hemoglobin separates to form Heme and Globin
- Heme becomes Iron and Biliverdin
- Iron goes to iron pool and globin goes to amino acid pool
- Unconjugated bilirubin combines with albumin and is taken to the liver
- unconjugated bilirubin is conjugated with glucuronic acid
- now water soluble, excreted in bile and feces
what do lipoproteins do?
transports lipids from intestines to other parts of the body.
what is the difference between VLDL and chilomicrons?
chylomicrons carry exogenous (dietary) products and VLDL carry endogenous products
order the lipoproteins from lowest density to highest
chylomicrons
VLDL
LDL
HDL
How does HDL differ from all the other lipoproteins?
- more:
- protein
- phospholipids
- fewer:
- free cholesterol
- cholesteryl esters
- triacylglycerols
- **for all other lipoproteins, all this increase as the lipoprotein gets more dense
how is cholesterol taken up into lipoproteins?
uptake via receptor mediated endocytosis
