Muscle fiber capacity in low conductivity solution.

A method is described for computing the effective capacity of muscle fibers, C = Q/V where Q is the charge stored, and V is the membrane potential, using a standard two-microelectrode, constant current injection technique. The method is used to compare physical (or effective) capacity of frog muscle fibers bathed in a low conductivity, 2.5 mMK+ solution, with circuittheory derived quantities in the same cells and in control fibers. No differences can be discerned and it is concluded that low conductivity of physiological solutions, per se, does not significantly reduce the length constant of frog muscle transverse tubules.