title: Interactions among epinephrine, thyrotropin (TSH)-releasing hormone, dopamine, and somatostatin in the control of TSH secretion in vitro.
abstract: Epinephrine and TRH independently release TSH from rat anterior pituitary cells in primary monolayer culture (ED50, 11 and 5 nM, respectively; maximum responses, 80% and 110%, respectively). The effects of these compounds together are additive, even at concentrations at which each is maximally effective alone. Dopamine inhibited basal and epinephrine-stimulated TSH secretion by 25 +/- 5% (+/-SE; ED50, 50 +/- 9 nM in each case). Somatostatin was effective against epinephrine-stimulated, but not basal, TSH secretion (80 +/- 4% inhibition; ED50, 1 +/- 3 nM). The data show that epinephrine is a potential regulator of TSH secretion by its own action and via its interactions with TRH, dopamine, and somatostatin.
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004298:Dopamine / Q000494:pharmacology*; D004347:Drug Interactions; D004837:Epinephrine / Q000494:pharmacology*; D007545:Isoproterenol / Q000494:pharmacology; D007700:Kinetics; D008297:Male; D010903:Pituitary Gland, Anterior / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013004:Somatostatin / Q000494:pharmacology*; D013972:Thyrotropin / Q000378:metabolism*; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology*
chemical_list: D013004:Somatostatin; D013973:Thyrotropin-Releasing Hormone; D013972:Thyrotropin; D007545:Isoproterenol; D004298:Dopamine; D004837:Epinephrine