7.4 Flashcards
how do the a, b, delta cells of pancreas interact with each other?
- gap junction
- blood flow
- innervation
delta cells produce
somatostatins
structure of preproinsulin
signal
A
B
connecting peptide
proinsulin structure
A
B
connecting peptide
(the signal was cleaved)
what happens to proinsulin once it gets to the ER?
folds
cooecting peptide is cleaved
connecting peptide and mature insulin are packed into secretory granules
how many units of insulin are secreted each day?
30-40 Units
which AA stimulate release of insulin?
Lys
Arg
Leu
which GLUT on pancreatic B cell?
affinity?
GLUT2
low affinity to glucose!
what happens to glucose when it gets into the cell?
phosphorylated by Glucokinas -> ATP production -> ATP will close ATP sens. K+ channels -> Depol -> voltage gated Ca++ open -> exocytosis of insulin
inhibitors of insulin secretion?
hypoglycemia SST leptin a2 adrenergic R FFA
which drug can help Type II DM?
Sulfonylurea
clode ATP sens K+ ch
to increase secretion of Insulin
what induces the Incretin effect?
GIP (Glucose Dependant Insulotropic Peptide)
GLP (Glucagon Like Peptide)
how glucaogen activated insulin secretion?
activates Gq to cause increase in Ca++ signal (which will cause secretion of insulin)
structure of insulin R?
2X a (extracellular) 2X b (intracellular)
job of the b subunit?
Tyrosine-Kinase activity
Insulin action in the body
- decreases blood glucose (hiiii GLUT4)
- decreases blood FA conc
- decreasse blood AA levels
- glycolysis
describe Type I DM
- Autoimmune process deteriorates B cells
(Insulin dependant) - no insulin production
- hyperglycemia
- no glycogen storage in muscles so protein degregation
- glucagon secretion is high bcs no negative feedback from insulin
- sweet urine
- osmotic diuresis
- diabetic ketoacidosis
describe Type II DM
non insulin dependant!!
insulin resistance
twice us much insulin to keep blood glucose normal
impared response to insulin
how can we diagnose DM?
Glucose tolerance test
Glycated Hg
C peptide
nornal blood glucose levels while fasting
5 mM
prediabetic blood glucose levels while fasting
6.1-7 mM
diabetic blood glucose levels while fasting
above 7 mM
