Clenbuterol-induced insulin resistance in calves measured by hyperinsulinemic, euglycemic clamp technique.
Hyperinsulinemic, euglycemic clamp tests were performed on calves before and after clenbuterol treatment. Clenbuterol was given as 2 intramuscular injections with an interval of about 12 h. The dose used was 1 microgram/kg b.w. The treatment resulted in increased plasma levels of insulin and glucose. The results of the clamp tests showed that clenbuterol induced a transient decrease in insulin sensitivity. Both insulin mediated glucose disposal (M), expressed as mumol/kg live b.w./min. and the M/I-index (M divided by the average insulin concentration at steady state) were significantly reduced after treatment. The effect of clenbuterol on carbohydrate metabolism seemed to be rather short-lived, since significant changes occurred only in animals treated 5-6 h prior to the test. According to the literature, the metabolic effects of clenbuterol have been studied only after the high doses used for growth promoting purposes. The results from the present study showed that similar changes occur also after doses at the therapeutic level. The hyperinsulinemic, euglycemic clamp test was considered to be a valuable tool for the study of insulin sensitivity in cattle.
Sternbauer
K
K
Department of Ruminant Medicine and Veterinary Epidemiology, Faculty of Veterinary Medicine, Swedish University of Agricultural Sciences, Uppsala University, Sweden. Karin.Sternbauer@idmed.slu.se
Luthman
J
J
Hänni
A
A
Jacobsson
S O
SO
D000818:Animals; D001786:Blood Glucose / Q000187:drug effects; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000494:pharmacology*; D002417:Cattle; D002418:Cattle Diseases / Q000139:chemically induced / Q000175:diagnosis* / Q000378:metabolism; D002976:Clenbuterol / Q000008:administration & dosage / Q000494:pharmacology*; D005947:Glucose / Q000008:administration & dosage / Q000378:metabolism; D015309:Glucose Clamp Technique; D006946:Hyperinsulinism / Q000139:chemically induced / Q000175:diagnosis / Q000378:metabolism / Q000662:veterinary*; D007273:Injections, Intramuscular; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008297:Male
D001786:Blood Glucose; D001993:Bronchodilator Agents; D007328:Insulin; D005947:Glucose; D002976:Clenbuterol