Abstract
The effect of the nitric oxide synthase inhibitor N G-nitro-l-arginine (l-NOARG; 100 µM) and the P2 purinoceptor antagonist pyridoxalphosphate-6-azophenyl-2’,4’-disulfonic acid (PPADS; 50 µM) was investigated on the non-adrenergic, non-cholinergic (NANC) relaxant response of the guinea-pig isolated taenia caeci to electrical field stimulation at 1 or 10 Hz, under isotonic recording conditions. Either drug alone caused an about 50% inhibition, while combining the two drugs nearly abolished the response at both frequencies. The inhibitory effect of l-NOARG (100 µM) was partly reversed by l-arginine (30 mM). PPADS, but not l-NOARG, inhibited the relaxant effect of exogenous ATP, but not that of the nitric oxide donor sodium nitroprusside. It is concluded that both nitric oxide and ATP are involved in the mediation of NANC relaxation in the taenia caeci, in an apparently additive manner.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received: 23 June 1998 / Accepted: 3 July 1998
Rights and permissions
About this article
Cite this article
Barthó, L., Lénárd Jr., L. & Szigeti, R. Nitric oxide and ATP co-mediate the NANC relaxant response in the guinea-pig taenia caeci. Naunyn-Schmiedeberg's Arch Pharmacol 358, 496–499 (1998). https://doi.org/10.1007/PL00005283
Issue Date:
DOI: https://doi.org/10.1007/PL00005283