Oesophageal peristalsis is controlled by vagal motor neurones, and intrinsic neurones have been identified in the striated muscle oesophagus. However, the effect(s) of intrinsic neurones on vagally-mediated contractions of oesophageal striated muscles has not been defined. The present study was designed to investigate the role of intrinsic neurones on vagally-evoked contractions of oesophageal striated muscles using hamster oesophageal strips maintained in an organ bath. Stimulation (30 µs, 20 V) of the vagus nerve trunk produced twitch contractions. Piperine inhibited vagally-evoked contractions, while capsaicin and N^G-nitro L-arginine methyl ester (L-NAME) abolished the inhibitory effect of piperine. The effect of L-NAME was reversed by subsequent addition of L-arginine, but not by D-arginine. L-NAME did not affect on the vagally-mediated contractions and presumed ³H-Ach release. NONOate, a nitric oxide donor, and dibutyryl cyclic GMP inhibited twitch contractions. Inhibition of vagally-evoked contractions by piperine and NONOate was fully reversed by ODQ, an inhibitor of guanylate cyclase. Immunohistochemical staining showed immunoreactivity for NO synthase (NOS) in nerve cell bodies and fibres in the myenteric plexus and presence of choline acetyltransferase and NOS in the motor end-plates. Only a few NOS-IR portions in the myenteric plexus showed vanilloid receptor 1 (VR1)-immunoreactivity. Our results suggest that there is a local neural reflex that involves capsaicin-sensitive neurones, nitrergic myenteric neurones and vagal motor neurones.