Bradykinin and angiotensin II inhibit neurotransmission in rabbit ear artery by releasing prostanoids.
In isolated, perfused rabbit ear artery bradykinin, like [Met5]enkephalin and angiotensin II, inhibited neurogenic constrictions in concentrations lower than 10(-8) M without affecting the responses to exogenous norepinephrine. The IC50 value of bradykinin was 1.95 x 10(-10) M. The inhibitory action of bradykinin and angiotensin II but not of [Met5]enkephalin was reduced or even reversed by indomethacin pretreatment, suggesting that endogenous prostanoids are involved.
Rónai
A Z
AZ
Institute of Organic Chemistry, L. Eötvös University, Budapest, Hungary.
D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D001158:Arteries / Q000187:drug effects / Q000294:innervation; D001920:Bradykinin / Q000494:pharmacology*; D004423:Ear / Q000098:blood supply; D004558:Electric Stimulation; D004744:Enkephalin, Methionine / Q000494:pharmacology; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000378:metabolism; D009638:Norepinephrine / Q000494:pharmacology; D011453:Prostaglandins / Q000378:metabolism / Q000494:pharmacology*; D011817:Rabbits; D012039:Regional Blood Flow / Q000187:drug effects; D009435:Synaptic Transmission / Q000187:drug effects*
D011453:Prostaglandins; D000804:Angiotensin II; D004744:Enkephalin, Methionine; D001920:Bradykinin; D009638:Norepinephrine; D007213:Indomethacin