Flashcards in Molecular Basis of Type 2 Diabetes Deck (15):
T/F insulin increases the volume of distribution of galactose
T --> increasing Vd by distributing glucose to muscle reduces plasma steady state glucose concentration
_____ is the insulin regulated rate limiting step to glucose metabolism
transport across plasma membrane
insulin upregulates # of glucose (glut4 - muscle/fat) transporters on cell membrane
What signals insertion of glut4 receptors into cell membrane?
insulin or muscle contraction
Implications of translocation hypothesis in T2D
glucose transport is insensitive to insulin but sensitive to contraction in T2D --> exercise can be effective in inducing glucose uptake
the inability of insulin to reduce hepatic output and stimulate glucose uptake in cells.
If you have a high blood sugar during fasting where is the defect?
in hepatic glucose output (because muscle uptake at fasting/in absence of insulin is close to 0)
If you have high blood sugar after eating, where is the defect?
Either resistance at the membranes of muscle cells preventing glucose uptake OR resistance at the liver preventing shutdown of glucose output
Insulin resistance on fat
rate of FA release into bloodstream increases
Impact of increased FA
liver produces more triglycerides
Why are fatty acids transported as VLDL and then broken down at the target site instead of just being transported as is?
In times of starvation, the volume of fatty acids being transported would lower the blood pH --> conversion increases carrying capacity of blood
Insulin resistance syndromes involve a ____ impairment in insulin action
selective --> e.g. liver should not produce triglycerides if insulin resistant --> possible that liver is insulin resistant in context of glucose but not in context of lipids
T/F Central obesity is a risk factor for T2D
T --> more of a factor than gynoid obesity
T/F BMI is a good indicator of adiposity
F --> people have different lean/fat ratios