pancreas Flashcards
(43 cards)
is the duodenal or splenic lobe of the pancreas thicker?
splenic
what type of hormone is insulin?
protein
where is insulin synthesized?
beta cells of the pancreas
- in the endoplasmic reticulum
what increases insulin productino?
- increased plasma [glucose]
- GI hormones
is insulin water-soluble?
yes
is insulin protein-bound?
no
main actions of insulin:
- anabolic
- metabolism of carbs, fats and proteins
release of insulin via
increased [calcium]i
insulin leads to what
- increased cellular glucose uptake
- increased synthesis of glycogen(liver), triglyceride(adipose), protein (muscle)
what GLUT is used by muscle and adipose tissue?
GLUT 4
what GLUT is used by neurons?
GLUT 3
what GLUT is used by erythrocytes?
GLUT 1
what GLUT is used by intestinal muscosal cells
GLUT2
synthesis of glycogen from glucose occurs where?
liver
synthesis of triglycerides fatty acids occurs where?
adipose tissue
synthesis of protein from amino acids occurs where?
muscle (due to increased AA uptake)
what is the most important factor controlling insulin release?
blood glucose
which produces a greater insulin response, oral glucose or blood glucose?
oral glucose
insulin is governed by a (+/-) feedback mechanism?
positive feedback
what decreases insulin secretion?
catecholamines
-via alpha-adrenergic receptors on beta cells
what input increases insulin release?
cholinergic input
the insulin:____ ratio is important
glucagon
what increases glucagon synthesis?
- catecholamines (e.g. EPI)
- glucocorticoids (e.g. cortisol)
- amino acids
what decreases glucagon synthesis?
- high plasma [glucose], [insulin]
- high plasma [free fatty acids]
