title: Effects of ovariectomy and exercise training on muscle GLUT-4 content and glucose metabolism in rats.
abstract: The present study examined the effects of 6 wk of ovarian endocrine deficiency on skeletal muscle GLUT-4 glucose transporter protein and glucose transport activity in sedentary and endurance-trained rats. Female Wistar rats (10 wk old) underwent bilateral ovariectomy (OVX) or sham surgery followed by a 5-wk swim-training protocol. OVX resulted in no significant changes in glycogen or GLUT-4 glucose transporter concentration in the soleus, epitrochlearis, or flexor digitorum brevis (FDB) muscles or in basal and maximally insulin-stimulated 2-deoxy-D-[1,2-3H]glucose (2-[3H]DG) transport in the soleus or epitrochlearis, suggesting that moderate-duration ovarian hormone deficiency does not significantly impair insulin action in skeletal muscle. In contrast, OVX decreased the maximal activation of 2-[3H]DG transport in the FDB by in vitro electrical stimulation. OVX had no significant effect on the training-induced changes in oxidative enzyme activities, GLUT-4 protein expression, glycogen content, or insulin-stimulated 2-[3H]DG transport in the soleus or epitrochlearis. These findings provide the first evidence that ovarian hormone deficiency decreases contraction-stimulated glucose transport in skeletal muscle.
authors.affiliation: Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
authors.forename: P A
authors.initials: PA
authors.lastname: Hansen
authors.forename: T J
authors.initials: TJ
authors.lastname: McCarthy
authors.forename: E N
authors.initials: EN
authors.lastname: Pasia
authors.forename: R J
authors.initials: RJ
authors.lastname: Spina
authors.forename: E A
authors.initials: EA
authors.lastname: Gulve
mesh_terms: D000818:Animals; D005260:Female; D005947:Glucose / Q000378:metabolism*; D007328:Insulin / Q000494:pharmacology; D009004:Monosaccharide Transport Proteins / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism*; D010052:Ovariectomy; D010805:Physical Conditioning, Animal; D051381:Rats; D017208:Rats, Wistar
chemical_list: D007328:Insulin; D009004:Monosaccharide Transport Proteins; D005947:Glucose