Influence of peristaltic contraction of distal colon on blood flow through colonic vein

Abstract

In experiments on dogs the influences of peristaltic contraction of the distal colon on blood flow through the colonic vein were studied. Blood flow was recorded continuously by electro-magnetic flow-meter.The peristaltic contraction of the distal colon caused the periodicity on the flow-meter tracing of the colonic vein.Three groups of the correlation between the peristaltic contraction and venous blood flow were observed. The first pattern is that the abrupt augmentation of the colonic blood flow was elicited during the contraction. The second pattern is that the diminution of colonic blood flow during the contractile phase was followed by the sustaining augmentation of the blood flow during the relaxation. The above mentioned two patterns being in combination is the third pattern. That is, the augmentation of the blood flow during the contraction was followed by the diminution of blood flow corresponding to the highest level of contraction and by the sustaining augmentation of blood flow during the relaxation. The third type was usually elicited by the stimulation of the pelvic nerve.The initial augmentation of blood flow is due to propulsive action on the blood within the colonic vessels. The secondary augmentation of blood flow is depended on the vascular dilatation which is caused by the obstruction of blood flow through the colon during the prolonged contraction.