Exam 4: Pancreas, Liver, And Gallbladder Flashcards
What are the two functions of pancreatic juice?
1) Neutralize acids from the stomach
2) provide enzymes for digestion of food
What enzymes are in pancreatic juice?
Amylase, lipase, and protease
What cells secrete the enzymatic components of pancreatic juice? What secretes the aqueous fraction?
Enzymatic component: Acinar cells
Aqueous fraction: centroacinar and Ducati cells
What happens to the composition of pancreatic juice as flow rate increases?
Bicarb increases while Cl decreases
What cells secrete CCK?
I cells
What cells secrete secretin?
S cells
What is the most important phase for pancreatic stimulation?
Intestinal phase
What stimulates release of CCK?
CCK is released from I cells in the intestinal phase in response to stimulation by fatty acids and amino acids in duodenal chyme
What does CCK do?
It travels to the pancreas and stimulates acinar cells to increase enzyme secretion (small effect on aqueous secretion)
What stimulates Secretin release?
Secretion is released from S cells in the intestinal phase in response to duodenal H+
What does secretin do?
Causes ductal cells in the pancreas to increase production of aqueous component of pancreatic juice, including HCO3,
-natures antacid
What role do phospholipids play in Bile?
- 20-40%
- no recirculating
- soluble in bile salts and increases ability of bile salts to solubilize cholesterol
In the digestive period, what stimulates the gallbladder to contract and the sphincter of Oddi to relax?
CCK and there is continuous bile duct secretion for as long as CCK is present
How are bile salts reabsored?
Na+ cotransport in the ileum
What are the 3 factors that factor gallstone formation?
Bile stasis, supersaturation of bile with cholesterol, and nucleating factors
