[Action of ketamine and hexenal on excitable membranes of a neuromuscular preparation in the frog].

The effects of the non-inhalation anesthetics, ketamine and hexenal (25 and 100 microM/l) on excitable membranes of the frog sartorius muscle were studied with the aid of intra- and extracellular electrodes. At the concentration 100 microM the anesthetics depressed most markedly the junctional transmission and practically had no influence on motor axon function. Since ketamine did not interact evidently with tubocurarine and showed pronounced antagonism to Mg ions, it is assumed that ketamine interferes with neuronally induced transmitter release.