pancreas Flashcards
what is adrenalines role in glucose production
is increased in fasting/exercise and then produces glucose
is hypoglycaemia associated with hypolipidaemia or hyperlipidaemia
hypolipidaemia
what are the essential molecular components of beta cell glucose sensing
- GLUT1/2
- glucokinase
- oxidative metabolism
- Katp channels
- L-type voltage-dependent calcium channels
- exocytotonic machinery
what does diazoxide do
forces Katp channels to open
what does tolbutamide do
forces Katp channels to shut
pathway of insulin production
- glucose in cell through GLUT1/2
- glucose converted to glucokinase
- this produces ATP
- ATP shuts Katp channel
- this makes calcium channel open
- this causes calcium to enter cell
- causing insulin to be released
what do beta cells respond to
- nutrients
- hormones
- neurotransmitters
can beta cells adapt to insulin resistance usually
yes
does type 2 diabetes cause beta cell apoptosis
yes
which type of cell is found the most in the pancreatic islets
beta
what does insulin driving anabolic pathways in target tissues cause to happen
it promotes storage of nutrients and lower blood glucose
what happens in alpha cells when glucose is low
- glucose uptake and metabolism low
- Katp channels open
- voltage gated sodium channels contribute to action potentials as sodium moves into cell
- calcium channels open then calcium influx
- glucagon exocytosis triggered
what happens in alpha cells when theres high glucose
- glucose uptake and metabolism high
- Katp channels closed
- cell depolarized
- presence of SGLT2 glucose transporters contributes to non-voltage-regulated sodium ion influx
- sodium and calcium channels closed, glucagon not released
what is the islet defect in T2DM
impaired insulin secretion
deregulated glucagon secretion
when is glucagon secretion elevated
in the fed state in T2DM
