Characterization of the effect of penehyclidine hydrochloride on muscarinic receptor subtypes mediating the contraction of guinea-pig isolated gastrointestinal smooth muscle

Objectives The aim was to characterize the effect of penehyclidine hydrochloride, which mediates the relaxation Of guinea-pig isolated gastrointestinal smooth muscle, oil muscarinic receptor subtypes. Methods Radioimmune assay was used to determine cAMP levels in isolated guinea-pig gastrointestinal Smooth muscle to compare the selective effects of penehyclidine hydrochloride oil muscarinic receptor subtypes. Key findings The results indicated that the relaxing effect of penehyclidine hydrochloride oil isolated gastrointestinal smooth muscle contraction induced by acetylcholine was stronger than that of atropine (based oil PA(2) values). In the radioimmune assay penehyclidine hydrochloride increased the cAMP content in isolated guinea-pig stomach smooth muscle and decreased the cAMP content in isolated guinea-pig intestinal smooth muscle, but the difference was not statistically significant at a close of 10 mu mol/l. Conclusions The results suggest that penehyclidine hydrochloride has little or no effect on M-2 receptor subtypes in guinea-pig gastrointestinal smooth muscle.