[Investigation of the oral-anal frequency gradient of the slow waves in the reversed intestinal segment].

Slow waves on small intestine are recognized by decreasing frequency from oral to anal direction. By means of an unipolar recording we found in 65,7 percent of our probes the higher frequency on oral side, in 15,7 percent on anal side and 18,6 percent no remarkable difference between both. After the reverse of a segment of small intestine we still found a reverse of the gradient of the frequences in that way, that nearly in the same percentage the higher frequency was now to be found on the anal side. The mechanical activity of the reversed segment remains also permanently reversed. These indicate that the oral-anal frequency gradient is bound causally to the direction of mechanical activity of the small intestinal wall. They further indicate the permanent antiperistalsis of the reversed small intestinal segment.