Pancreatic and Biliary secretion Flashcards
What type of secretory glands are found in the pancreas?
Both endocrine (into blood stream/lumen) and exocrine (into ducts)
what is produced from acinar cells?
digestive enzymes such as lipase and different amylases
what are produced from centro-acinar/duct cells?
electrolytes - bicarbonate ions
what does acidic chyme stimulate the release of?
electrolytes
What does protein rich chyme stimulate the release of?
Enzymes
What does fatty chyme stimulate the release of ?
Electrolytes and enzymes
what does secretin stimulate?
stimulates duct cells in the presence of acid = increased electrolytes
what does CCK stimulate?
stimulates acinar cells in the presense of fat or protein = lipase
what does the control of secretion involve?
lots of relflexes - same heirarchy sorta of gastric stimulation
what are the membrane specializations of the hepatocyte?
- two surfaces facine sinusoids - microvilli = bloodstream
- lateral surfaces bile canaliculi with microvilli = biliary tree = tight junctions
How many blood supplies does the liver have?
Dual - branch of hepatic artery, central vein and branch of portal vein
how are hepatocytes orientated?
with respect to vessles - the plates (one cell thick) are separated by sinusoids
what vessels drain the hepatocytes out of the liver?
hepatic vein and bile duct
what brings in new supplies for hepatocyte formation?
hepatic artery and portal vein (from stomach nutrient rich)
how does bile get to the gall bladder?
canaliculi - ductule - hepatic ducts - common hepatic duct - cystic duct - gall baldder
where does the bile duct open?
onto the major duodenal papillae with the pancreatic duct
what is the primary function of bile?
absorption and digestion of fat
what is in bile?
bile salts = digest fat
chloesterol
bile pigments = bilirubin
bicarbonate slution
what doe bile pigments do?
RBC breakdown
what do bile salts aggregate into?
Micelles with fat = hydrophobic core and a hydrophilic outer shell
what helps keep bile salts in solution?
cholesterol
what causes jaundice to present as yellow?
bilirubin from broken down haeme
what allows bile salts to be detergents?
steroid backbone is lipophilic and amino acid conjugate is hydrophilic = keep fats in solution in an aqueous environment = accessible to lipase
