THE RESPONSE OF INTACT INTESTINE IN NONANESTHETIZED DOGS TO CATHARTIC AGENTS AS INFLUENCED BY MORPHINE, ATROPINE AND STRYCHNINE

¹ From the Department of Pharmacology, Washington University School of Medicine, Saint Louis, Missouri

1. Morphine sulphate, when given orally in small doses, may actually increase the peristaltic activity of the small intestine.

2. Morphine sulphate in moderate amounts given orally increases the general tone of the small intestine and decreases peristaltic activity.

3. When small amounts of morphine sulphate are placed in the Thiry-Vella loop, absorption into the circulation takes place quickly and the tonus of the loop is increased; with small amounts increased amplitude of peristaltic contractions may be noted, but with moderate amounts the general tonus is quickly increased and sustained for hours. The penistaltic amplitude of the contraction with moderate and larger doses of morphine is also either decreased or abolished.

4. Morphine sulphate when given intravenously following a cathartic acts antagonistically to it. The decreased tone and powerful peristaltic contractions caused by the cathartic are abolished at once.

5. Atropine sulphate when given intravenously, following the intravenous administration of a cathartic agent, further decreases the general tonus and decreases the amplitude of the peristaltic contractions and in this manner diminishes the griping action of the cathartic drug.

6. The results from strychnine sulphate were so variable that no conclusions could be formed.