The action of diethyl ether has been studied on frog sciatic nerve-sartorius muscle preparations in vitro using modern single fiber techniques. At a concentration of ether which blocks the indirect twitch, the muscle fibers can be stimulated directly. They have normal resting potentials and the action potentials elicited show only minor changes in form. The neuromuscular block produced by ether is not effectively antagonized by edrophonium or succinylcholine. Ether causes reduction in the amplitude, and prolongation of the time course, of both the end-plate potential, and the miniature end-plate potential. Ether diminishes the sensitivity of the muscle postjunctional membrane to quaternary ammonium compounds such as carbamylcholine. The mechanism of the neuromuscular blocking action of ether differs from that of d-tubocurarine. It is suggested that ether causes changes in the behavior of the permeability controlling mechanisms which are engaged subsequent to receptor site activation.
(C) 1966 American Society of Anesthesiologists, Inc.