Correlation of Electrical and Mechanical Activity of Holothurian Muscle

Abstract

Spontaneous contractions of segments of an isolated longitudinal muscle of Holothuria cinerascens are not propagated across a sucrose gap. Asynchronous spiking and spontaneous depolarizations leading to contraction can be recorded independently on each side of the gap. Caffeine-induced contractures are not the result of depolarization. Depolarization with KCl temporarily restores contractility lost in a series of caffeine-induced contractures. Acetylcholine causes a depolarization which induces contraction. Individual muscle units may spike quite independently as depolarization progresses in a spontaneous contraction.