THE EFFECTS OF MORPHINE AND ITS DERIVATIVES ON INTESTINAL MOVEMENTS III. PERISTALSIS

¹ From the Laboratory of Pharmacology, University of Michigan Medical School, Ann Arbor, Michigan

Waves appearing on the records of intestinal movements recorded from a balloon may be associated with peristalsis if the ascending phase of the wave shows no maxima or minima and if there is evidence of nearly complete expulsion of water from the balloon. Usually muscular quiescence and sometimes muscular relaxation precede the constricting phase of peristaltic activity.

During the passage of a peristaltic wave over three balloons, under the experimental conditions of these experiments, 1400 to 1500 gram cm. of external work were obtained. The velocity of the waves varied from 2.7 to 19.5 mm. per second. The average power developed during peristaltic activity was of the order of 30 gram cm. per second.

Evidence is presented that the tone effects recorded from single balloons do not necessarily describe the activity at other points of the intestine, even at points less than 10 cm. from the balloon. Aside from the segmenting contractions there are disturbances which are only appreciable locally and others simultaneously involving long segments of the intestinal musculature.