BCM 475 Chapter Notes - Chapter 27: Branched-Chain Amino Acid, Acetyl-Coa Carboxylase, Adipose Tissue
Document Summary
Insulin = fed state | glucagon = starved state. Starved-fed cycle | 3 stages to maintain glucose homeostasis: well-fed state after meal, early fasting during night, re-fed state during breakfast (cid:3843). Fed condition = secretion of insulin | stimulates synthesis of proteins/storage of fuels. Trap large glucose qualities by glucokinase | glycogen synthesis. Limit glucose in blood by storing excess as glycogen and can release stored glucose when scarce. High km value = active only at high-glucose levels: forms glucose 6-phosphate at high-glucose levels. Glucose binding: phosphorylase a (active) phosphorylase b (inactive) Phosphorylase a = glucose sensor (also cleaves glycogen/glycogen breakdown) Glucose allosterically shifts glycogen system from degradative to synthetic mode. High insulin glucose entry into muscle/adipose tissue. Increases glucose entry into muscle for glycogen synthesis: promotes uptake of branched-chain amino acids (val, leu, iso, stimulates protein synthesis (muscle protein build-up) Liver: entry of glucose into adipose tissue provides glycerol 3-p for tag synthesis (cid:3844).
