Effect of Divinyl Oxide on Isolated Intestinal Muscle

Abstract

In the careful studies of Miller 1 on the effects of general anesthesia on the muscular activity of the gastro-enteric tract, it was shown that the relatively light anesthesia usually maintained with ethylene causes no marked changes in the tone or amplitude of contraction of intestinal muscles. On the other hand during the surgical stage of anesthesia with ether there is marked loss of tonus and almost complete inhibition of rhythmic and peristaltic contractions in stomach, small intestine, and colon. Divinyl oxide has been shown to have pharmacological properties resembling ethylene and ether, to which it is related chemically. 2 Its general physiological effects are less severe than those of ether, although it is a more powerful anesthetic agent. Since the action of divinyl oxide on intestinal movement has not yet been reported upon, it became of interest to determine what its relation might be to ether and ethylene in this regard.

Segments about 2 cm. long from the jejunum of a freshly killed rabbit were suspended by the Magnus method from a muscle lever, in oxygenated Locke's solution at 37.5° C. The drugs were added to the solution to saturation. Repeated trials were made with each drug in varying sequences of application on intestinal segments of 8 different rabbits.

Ether was always found to cause an immediate and marked loss of tone and inhibition of movement of such a muscle preparation (Fig. 1). Upon washing the ether out of the bath, normal tone and contractibility are promptly recovered. Ethylene bubbled to saturation in the bath was noted to cause a slight and transitory loss of the tone of the muscle, with occasional increase in amplitude of contraction (Fig. 2). Divinyl oxide added to saturation in the bath was observed uniformly to increase the tonicity of the intestinal segment.