Salivary responses to bethanechol and carbachol in mice

Abstract

The salivary responses to cholinergic drugs, bethanechol and carbachol, were examined in mice by using an improved method of Richiter’s. Bethanechol-induced salivation, with doses ranging from 0.8-3.2mg/kg, s,c., showed dose-dependent monophasic changes in the time-course pattern, while carbachol-induced salivation, with doses ranging from 0.4-1.6mg/kg, s. c., showed dose-dependent biphasic changes in the time-course pattern. Either phentolamine (10mg/kg, s. c.) or atropine (5mg/kg, s. c.) markedly inhibited an enhanced salivation induced by bethanechol or carbachol. These results show that an enhanced response of salivation to bethanechol and carbachol reflects the pharmacological property of these drugs. Probably, the nicotinic action may be related to the development of a biphasic pattern in carbachol-induced salivation.