title: Ageing, exercise and food restriction: effects on skeletal muscle glucose uptake.
abstract: We investigated the effects of ageing, exercise and food restriction on glucose uptake by muscles perfused with physiological concentrations of insulin and glucose in male Long-Evans rats. The rate of glucose uptake by hindlimb muscles perfused with medium containing 50 microU@ml insulin and 8 mM glucose was the same in 9-10 month-, 18 month-, and 24-month-old rats. Rats exercised by means of swimming 3 h/day, 5 days/week, had significantly higher rates of muscle glucose uptake than did the sedentary freely eating rats. Paired-weight sedentary rats, that were food restricted so as to keep their weights in the same range as those of the swimmers, had a hindlimb glucose uptake rate similar to that of the swimmers, and greater than that of the sedentary freely eating rats. The 24-month-old sedentary freely eating rats showed a trend toward a higher plasma glucose response and a lower plasma insulin response to a glucose tolerance test. The 24-month-old swimmers showed no deterioration in glucose tolerance compared to the 9-10 month-old rats. Our findings argue against the concept that ageing results in skeletal muscle insulin resistance in rats.
authors.affiliation: Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110.
authors.forename: J L
authors.initials: JL
authors.lastname: Ivy
authors.forename: J C
authors.initials: JC
authors.lastname: Young
authors.forename: B W
authors.initials: BW
authors.lastname: Craig
authors.forename: W M
authors.initials: WM
authors.lastname: Kohrt
authors.forename: J O
authors.initials: JO
authors.lastname: Holloszy
mesh_terms: D000375:Aging / Q000378:metabolism*; D000818:Animals; D001693:Biological Transport, Active; D001786:Blood Glucose / Q000378:metabolism; D005508:Food Deprivation / Q000502:physiology; D005947:Glucose / Q000493:pharmacokinetics*; D005951:Glucose Tolerance Test; D007333:Insulin Resistance / Q000502:physiology; D008297:Male; D009132:Muscles / Q000378:metabolism*; D005082:Physical Exertion / Q000502:physiology; D051381:Rats
chemical_list: D001786:Blood Glucose; D005947:Glucose