Corticosterone effect on insulin receptor number and kinase activity in chicken muscle and liver.
The effects of chronic corticosterone treatment (6 mg/kg/day) on insulin sensitivity and on liver and muscle insulin receptors were examined in 5-week-old chickens. The hypoglycemic effect of exogenous insulin was completely abolished within 2 weeks of treatment, suggesting a corticosterone-induced insulin resistance. Hepatic insulin receptor numbers were slightly reduced (P < 0.001) after 2 weeks of treatment. After 1 or 2 weeks, corticosterone treatment significantly reduced liver insulin receptor kinase activity toward the artificial substrate poly(Glu4,Tyr1). Muscle insulin receptor kinase activity was also significantly decreased after 1 week of treatment but this effect was accounted for by a decrease in basal activity. Therefore the corticosterone-induced insulin resistance is accounted for, at least in part, by altered hepatic receptor numbers and kinase activity. The impairment of muscle development involves postreceptor defects.
Taouis
M
M
INRA, Station de Recherches Avicoles, Nouzilly, France.
Derouet
M
M
Chevalier
B
B
Simon
J
J
D000273:Adipose Tissue / Q000187:drug effects; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D002645:Chickens; D003345:Corticosterone / Q000494:pharmacology*; D004435:Eating / Q000187:drug effects; D007328:Insulin / Q000097:blood; D008099:Liver / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D008297:Male; D009132:Muscles / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011972:Receptor, Insulin / Q000187:drug effects*
D001786:Blood Glucose; D007328:Insulin; D011505:Protein-Tyrosine Kinases; D011972:Receptor, Insulin; D003345:Corticosterone