Akademik Veri Yönetim Sistemi
Pharmacology, cilt.38, sa.1, ss.34-39, 1989 (SCI-Expanded)
Phenylephrine tested on the isolated endothelium intact rat aortic strips elicited an enhanced response in the second assay when compared with the response obtained in the first trial. Removal of the endothelium and the pretreatment of the strips in the endothelium with methylene blue almost completely prevented the enhanced response to phenylephrine in the second assay. Pretreatment of the strips with lysine acetyl salicylate failed to abolish the potentiated response to phenylephrine in the second test. These data were taken as an evidence that the basal production or release of endothelium-derived relaxing factor(s) but not cyclooxygenase products of arachidonic acid from the endothelium of the rat aorta can influence the contractile effect of phenylephrine and the enhanced response to this α-adrenoceptor agonist in the second assay is probably due to the reduced production or release of these endogenously occurring endothelium-originated substance(s).