Effect of physical training on glucose transporter protein and mRNA levels in rat adipocytes.
Physical training increases insulin-stimulated glucose transport and the number of glucose transporters in adipocytes measured by cytochalasin B binding. In the present study we used immunoblotting to measure the abundance of two glucose transporters (GLUT-4, GLUT-1) in white adipocytes from trained rats. Furthermore, the abundance of the mRNAs for these proteins and glucose transport was measured. Rats were swim-trained for 10 wk, and adipocytes were isolated from epididymal fat pads. The amount of GLUT-4/adipocyte volume unit was significantly higher in trained animals compared with both age- and cell size-matched animals. The amount of GLUT-4 mRNA was also increased by training and it decreased with increasing age. Furthermore, young age as well as training was accompanied by relatively low GLUT-4 protein/mRNA and relatively high overall GLUT-4 efficiency (recruitability and/or intrinsic activity). GLUT-1 protein and mRNA levels/adipocyte volume did not change with age or training.
Stallknecht
B
B
Department of Medical Physiology, Panum Institute, University of Copenhagen, Denmark.
Andersen
P H
PH
Vinten
J
J
Bendtsen
L L
LL
Sibbersen
J
J
Pedersen
O
O
Galbo
H
H
D019325:3-O-Methylglucose; D000273:Adipose Tissue / Q000166:cytology / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D051272:Glucose Transporter Type 1; D051275:Glucose Transporter Type 4; D008297:Male; D008757:Methylglucosides / Q000493:pharmacokinetics; D009004:Monosaccharide Transport Proteins / Q000235:genetics* / Q000378:metabolism*; D009124:Muscle Proteins; D009994:Osmolar Concentration; D010805:Physical Conditioning, Animal; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D051272:Glucose Transporter Type 1; D051275:Glucose Transporter Type 4; D008757:Methylglucosides; D009004:Monosaccharide Transport Proteins; D009124:Muscle Proteins; D012333:RNA, Messenger; C495679:Slc2a1 protein, rat; C495694:Slc2a4 protein, rat; D019325:3-O-Methylglucose