Comparative Sensitiveness of Blood Pressure and Intestinal Motility to Epinephrine.

Abstract

General anesthetics have long been known to depress motility of the gastrointestinal tract. This has recently been studied in some detail by Miller, 1 who reports that ether and chloroform have a very marked depressant effect. We have previously reported that the hemodynamic effect of epinephrine is materially altered by general anesthetics (ether). 2 Since previous studies on the comparative effect of epinephrine upon blood pressure response and gastrointestinal motility^3,4 have been made on animals under general anesthesia it seemed advisable to repeat this on the unanesthetized animal.

Dogs were used. Intestinal motility was recorded from fistulae of the jejunum by the balloon method. Carotid blood pressure was recorded from arteries previously transplanted externally to the skin. Epinephrine was injected intravenously by means of a Woodyatt pump for varying intervals of time from 2 to 10 minutes. Simultaneous records of blood pressure and intestinal motility have been obtained from 4 animals to whom neither anesthetics nor any drugs have been administered for 24 hours. In each instance a rise of blood pressure has been seen in the absence of intestinal inhibition. Simultaneous records have also been obtained in 6 animals to whom morphine has been administered, and in 1 animal to whom paraldehyde has been given. In each of the animals a rise of blood pressure was obtained without intestinal inhibition. In every instance a sufficient dose of epinephrine was effective in maintaining intestinal inhibition.