ELECTROMYOGRAPHICAL STUDIES ON THE FIBRILLARY TWITCHINGS ELICITED BY BIEDERMANN'S SOLUTION

(I) ITS SITE OF ORIGIN

Abstract

1. The nature of the fibrillary twitchings (BFT) elicited by Biedermann's fluid was studied. For the experiment, the sartorius muscle of the summer toad was used. The action potentials of BFT were observed by means of Sugi's septal method and bipolar leading.
2. To search the starting point of BFT, the site of origin, the impulse directions of BFT was discriminated by inspecting of them as well as by applying an impulse analyser, the septum being adopted at varying regions along the muscle. The result was that BFT originated, in the vivid muscle, from the narrow zone free from nerve endings, which situated 1/6-1/8 of the entire muscle length from the pelvic end.
3. Comparing the usual voltages of BFT with that of a fascicule's twitching whose fibers in number was not more than a motor unit, it was obtained that the former amounted to 1/2.5-1/5 of the latter. Thus the unit in action of BFT is presumed to involve almost 6-12 muscle fibers.
4. Any region brought in catelectrotonic state seize the superiority, becominga pace maker, and cutting and pressure influenced temporary on it. But as to the cutting, Biedermann's fluid should act one the intact surface, not in the exposed interior of the muscle.