The effect of hypoxia on the electrical slow wave of the canine small intestine

The effect of 4 hr. of localized hypoxia on the electrical activity of intact intestinal segments of unanesthetized dogs was investigated through the use of indwelling platinum electrodes. Slow-wave activity from normal intestinal segments orad and caudad to the perfused segments was conducted only for short distances into the perfused segment. The frequency of the slow waves in the center of the perfused segment was less than the frequency in segments orad or caudad to it. When the influence of the upper duodenal pacemaker was removed from lower duodenal and upper jejunal segments by hypoxic perfusion, the direction of conduction of the slow waves in these lower, non-perfused segments was orad, caudad, or both.