Insulin stimulation of iodothyronine 5'-deiodinase in rat brown adipocytes.
Insulin (100-3333 microU/ml) stimulates iodothyronine 5'-deiodinase 3 to 4 fold in dispersed rat brown adipocytes. Deiodinase activity increased steadily from 1 to 4 hours. Insulin increased enzyme activity via an increase in the Vmax while the Km remained unchanged. Omission of glucose from the medium did not affect the insulin response. Studies with alpha-amanitin suggested that the increase in deiodinase activity was not due to an increase in the rate of transcription. The insulin effect was not additive to that of alpha 1-catecholamines, suggesting the two stimulators might have one or more common elements.
D002001:Adipose Tissue, Brown / Q000187:drug effects / Q000201:enzymology*; D000818:Animals; D002478:Cells, Cultured; D005947:Glucose / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology*; D007453:Iodide Peroxidase / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
D007328:Insulin; D007453:Iodide Peroxidase; D005947:Glucose; D009638:Norepinephrine