We examined the effect of KW-5092, a gastroprokinetic agent with acetylcholinesterase inhibitory and acetylcholine release facilitatory activities, on the peristalsis of isolated guinea pig ileum. KW-5092 (10(-9)-3 x 10(-6)M) increased the frequency of the peristaltic wave without changing its amplitude. Neostigmine increased the frequency at 10(-7) M, but domperidone (10(-8)-3 x 10(-6)M) had no effect on the peristalsis. The present results suggest that KW-5092 enhances the peristalsis via the inhibition of acetylcholinesterase, resulting in the intestinal propulsion.