Inhibitory influences of vagal afferences on the oesophageal EMG peristaltic pattern

The influence of vagal afferents on the EMG peristaltic pattern was studied in pigeon oesophagus. Bilateral vagotomy did not abolish the primary peristalsis, but induced significant modifications of the peristaltic pattern parameters. Vagal afferent stimulation induced an inhibitory effect consisting of a temporary break or definitive block of the EMG peristaltic activity already in progress. Vagal afferent stimulation also induced a reduction of the spontaneous EMG activity and this effect was abolished either by glossopharyngeal bilateral section or ganglionic block. Likewise vagal afferent stimulation, the crop distension caused inhibitory effects on EMG peristaltic pattern. This effect was abolished by bilateral vagotomy. These results indicate that vagal afferents, originating from the crop, could influence the central neurons responsible for the peristaltic motor programme.