Membrane Resting Potential of Denervated Mammalian Skeletal Muscle Measured in Vivo

Abstract

The membrane resting potential was measured by means of an intracellular microelectrode in the denervated tibialis anterior muscle of living, anesthetized white mice. Expts. were done on 29 animals, which had been denervated for periods ranging from 20 hrs. to 50 days. After denervation avg. resting potential remains near its normal level of approx. 100 mV. for about 2 days. It then falls rapidly, reaching about 90 mV. at 3 days, and 80 mV. after 10 days denervation. Further fall in resting potential is slight, the value being about 77 mV. after 50 days. In 4 expts. the resting potential in the denervated muscle was compared with that in the contralateral normal one. In each case the P value was much less than 0.001.