title: Effect of glibenclamide on thyroid hormone metabolism in rats.
abstract: This study was undertaken to elucidate the effect of glibenclamide, one of sulfonylurea drugs, on thyroid hormone metabolism in vivo and on the conversion of thyroxine (T4) to 3,5,3'-triiodothyronine (T3) in the isolated perfused rat liver and kidney. Glibenclamide (0.2 mg/kg body weight) was intraperitoneally administered to normal and streptozotocin-induced (50 mg/kg) diabetic rats for 14 days. The liver and kidney of normal rats were perfused for 30 minutes with a synthetic medium containing 20 micrograms/dl T4 and glibenclamide (200 or 400 ng/ml), and production of T3 in the tissues was measured by radioimmunoassay. Serum T4 and T3 levels in control and streptozotocin-induced diabetic rats were not changed by daily intraperitoneal glibenclamide administration. The production of T3 (111 +/- 40 and 95 +/- 16 ng/g/30 min, mean +/- SD) and the conversion rate of T4 to T3 (11.1 +/- 2.9 and 10.2 +/- 2.3%) in the liver perfused with glibenclamide (200 and 400 ng/ml) were not significantly different from those in controls (109 +/- 41 ng/g/30 min and 12.8 +/- 5.4%). And those (120 +/- 33 and 99 +/- 19 ng/g/30 min, and 3.5 +/- 0.6 and 2.5 +/- 0.4%) in the kidney perfused with glibenclamide (200 and 400 ng/ml) were similar to those in controls (98 +/- 33 ng/g/30 min and 3.0 +/- 1.5%).
mesh_terms: D000818:Animals; D003920:Diabetes Mellitus / Q000378:metabolism; D005905:Glyburide / Q000008:administration & dosage / Q000494:pharmacology*; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains / Q000145:classification; D013963:Thyroid Hormones / Q000378:metabolism*; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
chemical_list: D013963:Thyroid Hormones; D014284:Triiodothyronine; D013974:Thyroxine; D005905:Glyburide