title: Relaxation of bovine, porcine and human brain arteries by parathyroid hormone.
abstract: We have studied the relaxant effect of bovine parathyroid hormone (bPTH) on helical strips of branches of bovine and human middle cerebral arteries and bovine and porcine basilar arteries. All arteries were studied after contraction with prostaglandin (PG) F2 alpha or KCl. In the case of all arteries contracted with PGF2 alpha, the ED50 of PTH vasorelaxation related to maximal vasorelaxation induced by papaverine ranged from 9 to 14 nM for bPTH-(1-34) and 100 to 220 ng/ml for native bPTH-(1-84). The PTH inhibitor, [Nle8, Nle18, Tyr34]bPTH-(3-34) amide, attenuated the vasorelaxant effect of both bPTH-(1-34) and bPTH-(1-84). The vasorelaxant effects of PTH which we have observed in this study are consistent with the stimulatory effects of PTH on vascular adenylate cyclase which we had previously reported.
mesh_terms: D000328:Adult; D000818:Animals; D001158:Arteries / Q000187:drug effects*; D002417:Cattle; D002536:Cerebral Arteries / Q000187:drug effects*; D000242:Cyclic AMP / Q000502:physiology; D006801:Humans; D010281:Parathyroid Hormone / Q000378:metabolism / Q000494:pharmacology*; D011817:Rabbits; D051381:Rats; D013552:Swine; D014661:Vasoconstriction / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects
chemical_list: D010281:Parathyroid Hormone; D000242:Cyclic AMP