Exercise modulates the insulin-induced translocation of glucose transporters in rat skeletal muscle.
Insulin and acute exercise (45 min of treadmill run) increased glucose uptake into perfused rat hindlimbs 5-fold and 3.2-fold, respectively. Following exercise, insulin treatment resulted in a further increase in glucose uptake. The subcellular distribution of the muscle glucose transporters GLUT-1 and GLUT-4 was determined in plasma membranes and intracellular membranes. Neither exercise nor exercise----insulin treatment altered the distribution of GLUT-1 transporters in these membrane fractions. In contrast, exercise, insulin and exercise----insulin treatment caused comparable increases in GLUT-4 transporters in the plasma membrane. The results suggest that exercise might limit insulin-induced GLUT-4 recruitment and that following exercise, insulin may alter the intrinsic activity of plasma membrane glucose transporters.
Douen
A G
AG
Division of Cell Biology, Hospital for Sick Children, Toronto, Ontario, Canada.
Ramlal
T
T
Cartee
G D
GD
Klip
A
A
D000818:Animals; D015153:Blotting, Western; D002462:Cell Membrane / Q000378:metabolism; D003571:Cytochalasin B / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D007328:Insulin / Q000494:pharmacology*; D008297:Male; D009004:Monosaccharide Transport Proteins / Q000378:metabolism*; D009132:Muscles / Q000187:drug effects / Q000378:metabolism*; D005082:Physical Exertion / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains
D007328:Insulin; D009004:Monosaccharide Transport Proteins; D003571:Cytochalasin B; D005947:Glucose