In this article we studied whether the nitrergic relaxation of the rabbit sphincter was sensitive to glibenclamide. Field stimulation relaxed the sphincter of Oddi rings after incubation with atropine (1 microM) and guanethidine (4 microM) with threefold and fourfold increases in tissue guanosine 3':5'-cyclic monophosphate and adenosine 3':5'-cyclic monophosphate contents, respectively. These changes were blocked by 30 microM NG-nitro-L-arginine methyl ester. Glibenclamide (0.1-10 microM) attenuated the field stimulation-induced relaxation and completely abolished the relaxation produced by 0.1 microM cromakalim. We conclude that nitrergic relaxation of the rabbit sphincter of Oddi comprises a mechanism sensitive to glibenclamide.
Copyright 1997 The Italian Pharmacological Society.