Inhibition of dopamine-induced release of growth hormone by thyrotropin-releasing hormone.
The effects of thyrotropin-releasing hormone (TRH) and dopamine (DA) on serum growth hormone (GH) levels were examined in the adolescent male baboon. Intravenously administered DA (40 microgram/kg-min-1 for 20 min) raised serum GH and glucose and lowered serum insulin concentrations but caused no increase in blood pressure. Concomitant intravenous infusion of TRH at 2 doses (96 ng/kg-min-1 and 40 microgram/kg-min-1 for 20 min) blocked the DA-induced increase in serum GH. The relatively low effective doses of TRH used to suppress the DA-induced GH increase suggest an interaction with catecholamines at the hypothalamic and/or pituitary to influence GH release.
D000818:Animals; D001786:Blood Glucose; D001794:Blood Pressure / Q000187:drug effects; D004298:Dopamine / Q000494:pharmacology*; D018492:Dopamine Antagonists; D013006:Growth Hormone / Q000097:blood*; D000882:Haplorhini; D007328:Insulin / Q000097:blood; D008297:Male; D010215:Papio; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology*
D001786:Blood Glucose; D018492:Dopamine Antagonists; D007328:Insulin; D013973:Thyrotropin-Releasing Hormone; D013006:Growth Hormone; D004298:Dopamine