Abstract
The mechanism of the anaphylactic contraction of smooth muscle have ever been discussed by several investigators. But the fundamental question have never been solved clearly; whether the anaphylactic contraction of smooth muscle can be produced by the direct effect of antigen-antibody reaction on the cell membrane and/or on the contractile elements in the cell or not? This is the most interesting and without dealing with it, anaphylactic contraction is hardly said to be completely studied. Some problems have recently been brought foreward in the “chemical mediator theory”. Many substances are advocated as “chemical mediators”, acetylcholine, histamine, serotonin, bradykinin, slow reacting substance in anaphylaxis, plasmine, ATP and so on (1, 2). There is, however, no established view as to what is essential in anaphylaxis, and whether it is a single or plural. The chemical mediator theory seems to be supported only the fact that in anaphylaxis, endogenous chemical substances are increased in blood over the normal level, and that the symptom in anaphylaxis is resemble with that introduced by administration of such a substance.
On the other hand, the observations in the electrophysiological study have recently given me some important informations about a relation between excitability of cytoplasmic membrane and muscular contraction (3-8). In 1958, Evans et al. (9) reported that acetylcholine, histamine and serotonin could induce contraction of the smooth muscle even which cytoplasmic excitability was abolished by the “isotonic potassium-Ringer”. The present work was undertaken to elucidate this point in anaphylactic contraction in smooth muscle and for this purpose, changes in membrane potential and tension of the muscle were recorded during antigen-antibody reaction in the medium added potassium ion excessively.
