Effects of prostanoids on isolated feline cerebral arteries. I. Characterization of the contraction-mediating receptor.
The effects of various prostanoids on isolated feline basilar arteries (BA) were studied. Contractions were induced with the following order of potency: U 46619 approximately equal to U44069 greater than PGB2 greater than PGF2 alpha approximately equal to PGA2 approximately equal to PGB1 greater than or equal to PGA1 approximately equal to PGE2 = PGD2 greater than PGF1 alpha approximately equal to TXB2 approximately equal to PGE1 approximately equal to PGD1. Distinct bimodal responses with a relaxation at low concentrations followed by a contraction at high concentrations, were induced by PGA1, PGA2, PGD, and PGE2. None of the tested prostanoids relaxed K+-contracted arteries, and a sizable relaxant effect in PGF2 alpha-contracted arteries could be induced only by PGE1. As judged by the relative order of potency, PG-induced contractions of the feline BA seem to be mediated by a thromboxane sensitive receptor. PGF2 alpha-induced contractions apparently do not involve the release of noradrenaline from perivascular nerves since phentolamine failed to affect contractions induced by this agent.
D000818:Animals; D001488:Basilar Artery / Q000187:drug effects*; D002415:Cats; D005260:Female; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D009638:Norepinephrine / Q000378:metabolism; D011453:Prostaglandins / Q000494:pharmacology*; D011956:Receptors, Cell Surface / Q000187:drug effects*; D011982:Receptors, Prostaglandin / Q000187:drug effects*
D011453:Prostaglandins; D011956:Receptors, Cell Surface; D011982:Receptors, Prostaglandin; D009638:Norepinephrine