Contractility of muscle in solutions of low electrolyte concentration

Abstract

Spontaneous activity of the frog's stomach muscle ceased after immersion in isosmotic sucrose solution, but was restored after the addition of a small amount of CaCl₂. Similarly, the sartorius which had become nonexcitable in sucrose solution gave nonconducted responses on electric stimulation after the addition of about 1 mM CaCl₂. As an explanation of excitatory phenomena in nearly electrolyte free solutions it is suggested that the responses are due to activation of an intracellular conduction mechanism.