15 - GI Accessory Organs Flashcards
What are the lobes of the liver
quadrate
right
caudate
left
How do the product s of hte liver, gallbladder and pancreas travel through ductwork
right and left hepatic duct
common hepatic duct from liver
(cystic duct from gallbladder)
common bile duct
(pancreatic duct from pancreas
hepatopancreatic ampulla
hepatopancreatic sphincter
What are the cell types of the liver
hepatocytes
- perform functions of the liver
macrophages
- phagocytose microbes and toxins and help break down work out RBCs and WBCs
- secrete proinflammatory cytokines
What are the functions of the liver
- processing
- carbs, fats, aa, vitamins - synthesis of proteins
- processing drugs and hormones
- storage of iron and excretion of bilirubin
- Fat digestion
How does the liver process aa
essential amino acids used for protein synthesis
liver converts toxic ammonia to urea –> can then be excreted by the kidneys
How does the liver process dietary lipids
packages fats into forms that can be transported to and from tissues (lipoproteins)
- VLDL, LDL, HDL
What are the vitamins processed by the liver do
A –> converted to retinyl esters (vision)
D –> bone metabolism/Ca absorption
E –> antioxidant
K –> utilized by hepatocytes to form functional coagulation factors
What plamsa proteins does the liver syntehsize
albumin
coagulation factors
complement proteins
Where is iron found in the body
in hemoglobin of RBC
liver stores 10% of the total body iron on a ferettin
- delivers iron from the liver to the bone marrow bound to transferrin
heme discarded as bilirubin
What is bile used for
lipid digestion and absorption
cholesterol metabolism
excretion of lipid-soluble drugs
What is bile composed of
bile acids (salts) – emulsification
cholesterol
bilirubin
electrolytes
What is the gallbladder
thin green sack with muscular wall
bile concentrated and stored until needeed
cholesterol in bile can precipitate to form gallstones
How is bile production and storage regulated
parasympathetic stimulation (vagus nerve)
- enhances hepatic bile production
- weak contractions of the gallbladder
CCK
- intense contractions of the gallbladder
secretin
- enhances hepatic production of bicarbonate-rich bile
How is endocrine function regulated
changes in blood chemistry and neural input
parasympathetic
- release of insulin (decreased glucagon release)
sympathetic
- release of glucagon (decreased release of insulin)
How is exocrine function regulated
neural and hormonal mechanisms
parasympathetic
- release of pancreatic juice
secretin
- secretion of bicarbonate-rich pancreatic juice
CCK
- secretion of enzyme-rich pancreatic juice
