PT - JOURNAL ARTICLE AU - James L. Ellis TI - Role of Soluble Guanylyl Cyclase in the Relaxations to a Nitric Oxide Donor and to Nonadrenergic Nerve Stimulation in Guinea Pig Trachea and Human Bronchus DP - 1997 Mar 01 TA - Journal of Pharmacology and Experimental Therapeutics PG - 1215--1218 VI - 280 IP - 3 4099 - http://jpet.aspetjournals.org/content/280/3/1215.short 4100 - http://jpet.aspetjournals.org/content/280/3/1215.full SO - J Pharmacol Exp Ther1997 Mar 01; 280 AB - The effect of the novel, selective, soluble guanylyl cyclase inhibitor 1H-[1,2,4]oxadiazolol[4,3-a]quinoxalin-1-one (ODQ) on the nitric oxide component of the nonadrenergic, noncholinergic relaxation in guinea pig trachea was examined. Relaxant responses to field stimulation (1-16 Hz, 8 V, 1 ms for 15 s) in the presence of indomethacin (3 μM), atropine (1 μM), propranolol (1 μM), α-chymotrypsin (2 U/ml) and histamine (3 μM) were partially inhibited by 0.1 μM ODQ and almost abolished by 1 μM ODQ. In addition, relaxations to the nitric oxide donor 3-morpholinosyndnonimine-N-ethylcarbamide were partially inhibited by 0.1 μM ODQ and abolished by 1 μM ODQ. Relaxations to 3-morpholinosyndnonimine-N-ethylcarbamide in human bronchus were also substantially inhibited by ODQ (1–10 μM). By contrast, relaxations elicited by the stable 3′,5′-cyclic monophosphate analog 8-bromoguanosine-3′,5′-cyclic monophosphate and by isoproterenol were unaffected by 1 μM ODQ in guinea pig trachea and by 10 μM ODQ in human bronchus. These results suggest that relaxant responses to endogenously released or exogenously added nitric oxide in guinea pig trachea and human bronchus are mediated via the activation of soluble guanylyl cyclase and the formation of guanosine-3′,5′-cyclic monophosphate. The American Society for Pharmacology and Experimental Therapeutics