Distension-induced myoelectrical dysrhythmia and effect of intestinal pacing in dogs

The aims of this study were to investigate the effect of duodenal distension on intestinal myoelectrical activity and to investigate whether intestinal pacing was able to reverse the effects of distension. Six female hound dogs with four pairs of electrodes on the proximal jejunum were involved in this study. The protocol consisted of 30 min of recording of jejunal myoelectrical activity as baseline and 90 min of recording during distension. Intestinal pacing was performed during the second 30 min of distension. Duodenal distension severely impaired intestinal myoelectrical activity. The percentage of normal slow waves was reduced from 90.8+/-8.4% at baseline to 73.8+/-10.2%, 57.2+/-11.4%, and 53.7+/-16.0% during the first, second and third 30 min of distension (P<0.05, ANOVA). The dominant power was similarly decreased and the minute-by-minute variation of dominant frequency was significantly increased after distension. Intestinal pacing reversed distension-induced dysrhythmia. The percentage of normal slow waves during the 30 min of distension with pacing was significantly higher than the corresponding 30 min of distension without pacing (88.5+/-6.6% vs. 57.2+/-11.4%, P<0.03). It was concluded that intestinal pacing can normalize distension-induced dysrhythmia and has a potential as a future therapeutic modality for intestinal motor disorders.