Physiology - Liver Flashcards
what hormones are deactivated by the liver?
insulin
glucagon
ADH
steroid hormones
what hormones are activated by the liver?
thyroid hormone
vitamin D
what effect does the liver have on thyroid hormone?
converts T4 to more active T3
what effect does the liver have on vitamin D?
converts it to 25-hydroxy vitamin D aka calcifediol
this is then converted to calcitriol (final active form) in the kidney
what things are stored in the liver?
fat soluble vitamins water soluble vitamin B12 iron copper glycogen
name the four fat soluble vitamins?
A
D
E
K
what proteins are synthesised by the liver?
coagulation factors albumin complement proteins apolipoproteins carrier proteins
what coagulation factors are synthesised in the liver?
II VII IX X proteins C+S
what are the phagocytes in the liver called?
kupffer cells
what is the role of kupffer cells?
destroy particulate matter and old erythrocytes
where is bile secreted from?
hepatocytes
cholangiocytes (bile duct cells)
what happens to bile in between meals?
stored and concentrated in the gallbladder
describe the state of the sphincter of oddi in between meals
closed
to keep bile in the gallbladder
what stimulates the gallbladder to contract during a meal?
chyme in the duodenum
via CCK and vagal impulses
what happens to bile during a meal?
sphincter of oddi opens and bile moves into the duodenum via cystic and common bile ducts
what does the primary juice secreted by hepatocytes into biliary ducts contain?
primary bile acids water electrolytes lipids cholesterol IgA bilirubin metabolic waste
what are the primary bile acids?
cholic acids
chenodeoxycholic acids
what is bilirubin?
breakdown product of the porphyrin component of haemoglobin
what is the best treatment for symptomatic gallstones?
laparoscopic cholecystectomy
what drug can be given for small unproblematic gallstones?
ursodeoxycholic acid
what is an adverse effect of ursodeoxycholic acid?
diarrhoea
what drugs can be given to relieve biliary spasms?
atropine
GTN
what happens to the vast majority of bile salts that enter the duodenum?
reabsorbed in the terminal ileum to undergo enterohepatic recycling
small amount excreted in faeces
