Reciprocal contraction of antagonistic muscles in peripheral preparations, using flashing neon-lamp circuit for excitation of nerve

Abstract

In a previous communication by one of us (G. B. (1)) it was shown that graded contractions and relaxations of natural form can be obtained in the diaphragm and in skeletal nerve muscle preparation by manipulating a faradic induction apparatus in a special manner. Briefly, this manipulation consists in imparting a smooth to-and-fro movement to the secondary coil of the apparatus, the movement taking place between the points of just maximal and just minimal stimulation. These to-and-fro movements cause certain changes of amplitude in the stimulating current, and the various patterns thus produced are faithfully repeated in the contractions of the experimental muscle, provided the changes are kept within the above-mentioned limiting points. An attempt has been made in the present research to obtain reciprocal contraction of antagonistic muscles by an extension of the above method. In the working-out of the new method of excitation, and in its application to double nerve-muscle preparations, the physiological experiments have been done by one of us (G. B.) and the physical by the other (W. L.).