Pirenzepine inhibits acid and pepsinogen secretion by the isolated perfused mouse stomach

Acid and pepsinogen secretion were studied in the isolated luminally perfused mouse stomach. Stimulation was obtained with bethanechol 10(-5)M. Pirenzepine blocked the effect of bethanechol in a dose dependent manner. The minimal blocking dose was 10(-5)M. Atropine 10(-6)M blocked secretion to a similar extent as pirenzepine 10(-5)M. Addition of tetrodotoxin did not change the response to bethanechol or to bethanechol together with pirenzepine. It is concluded that acid and pepsinogen secretion stimulated by bethanechol are inhibited by atropine and pirenzepine. There is at present no evidence that bethanechol stimulation or antimuscarinic inhibition act via intramural nerves.