A Comparison of the Effects of Three Organic Solvents: Dimethyl Sulfoxide, Formamide, and Propylene Glycol, on Spontaneous Activity of Isolated Smooth Muscle

Abstract

The effects of propylene glycol, formamide, and dimethyl sulfoxide on the contractility of isolated smooth muscle preparations of uterus, duodenum, and rectum were studied. The recording technique employed provided information about the effects of the compounds on the frequency and amplitude of contractions of two types of waves. All three compounds depressed the amplitude of the contractions. In the case of dimethyl sulfoxide, this action can be attributed to metabolic changes. The changes produced in frequency of contraction of duodenum could be attributed to direct membrane phenomena and changes induced through a nervous interaction. In the case of the uterus and rectum, the membrane mechanisms seemed to be either directly affected or secondary to metabolic action. It is concluded that these agents are not pharmacologically inert since they possess pharmacological properties of their own.