export_endocrinology Flashcards
(117 cards)
What factors stimulate insulin secretion?
- plasma aa
- GI hormones (CCK, gastrin etc) feed forward effect
- psymp activity
What % of insulin secretion is due to ‘feed forward;’effect
80%
Name 4 catabolc hormones
- glucagon
- GH
- cortisol
- catecholamines
What effect does insulin have?
increased:
- glucose oxidation
- lipogenesis
- glycogensis
- protein synthesis
What does glucagon do?
Increases:
- gluconeogenesis
- glycogenolysis
- ketogenesis
What glucose transporter is req in skeletal muscle?
GLUT 4
What is adipocytes response to insulin?
insert GLUT4 trans into membrane
What is glucose transformed to in the cell?
G-6-P
Glycogen
Fat
What glucose transporter ispresent in the liver?
GLUT 2
what does insulin stimulate in the hepatocyte?
hexokinase which converts –> G6P
Why is constant blood glucose vital for neurone?
they cannot regulate amount of glucose in CSF and the transport of glucose in/out is steady.
If CSF = plasma and glucose v high - dehydrate; if v low - starve
Are neurones sensitive to insulin?
NO
What efect does insulin have on K+?
inc K+ uptake into cells by providing ATP. It activates NaKATPase pump
What type of insulin is identical to dogs?
Pigs
What is cow insulin similar to?
Cats
How does insuln react with cells?
Binds to tyrosine kinase receptor
Where is insulin metabolised?
Liver and kidney
Which species often metabolises insulin fastest?
cats
What is crystalline zinc insulin?
recomb DNA
phosphate buffer
VERY RAPID ACTION
What is lente insulin?
insoluble - in acetate
No protamine
What type of insulin is found in canisulin
Lente insulin
What is the purpose of protamine zinc insulin?
Slow absorption and action. Large zinc crystals
What is insulin glargine?
v large precipitate. human. pos in cats.
From fastest to slowest name insulin formulations
- soluble
- semilente
- isophane
- lente
- protamine zinc
- glargine