Hellekant Pancreas Flashcards
Insulin inhibits breakdown of fat/adipose by inhibiting what enzyme?
Intracellular lipases that hydrolyze TGs
What are the effects of sympathetics on beta islet cells?
Inhibit insulin and amylin secretion
Parasympathetic nerves via the vagus n. Are involved in what phase of insulin secretion?
Cephalic phase
What cells secrete glucagon?
Alpha islet cells
What cells of the pancreas secrete somatostatin?
Delta cells
What is amylin?
Amino acid that is Co-packaged and co-secreted with insulin in beta cells
What is the function of amylin?
Inhibits glucagon secretion (at alpha cell); induces satiety, delays gastric emptying, inhibits secretion of digestive enzymes
Glucagon increases in response to what?
Hypoglycemia, amino acids, and sympathetics
What triggers the release of somatostatin in regards to pancreatic hormones?
Insulin
What inhibits release of somatostatin in regards to pancreatic hormones?
Ghrelin
What cells release ghrelin?
Epsilon
What is the function of somatostatin in regards to pancreatic functions?
Inhibits release of insulin, glucagon, and ghrelin.
What are examples of incretins? What is their broad function?
GIP, and GLP-1; promote beta cell insulin release after eating
What cells produce GLP-1?
L cells
What is the function of GLP-1?
Stimulates insulin in high glucose situation and inhibits glucagon secretion euglycemia or hypoglycemia
What degrades glp-1?
Dipeptidyl peptidase -4
What cells produce GIP?
K cells
What is the function of GIP?
Stimulates insulin in high glucose situation and promotes glucagon secretion following a meal
How is GLP-1 formed?
Alternative splicing from glucagon gene
What is the function of dipeptidyl-peptidase 4?
Degradation of GLP-1
What is a big difference in the effects of GLP-1 vs. GIP?
GLP-1 decreases PP glucagon, while GIP increases PP glucagon
During what phase are the incretins released? What causes the release?
GI phase; released due to hyperosmolarity due to glucose in gut
Why is there a larger insulin response from oral vs. IV glucose?
Due to oral (carbs stimulate sweet receptors) and intestinal (incretins released) phases of insulin secretion
Where are SGLT1 transporters found?
Mostly small intestine; if in kidney fond in late proximal straight tubule
Where are SGLT2 transporters found?
Kidney - early PCT