Intra-Axonal Injection of Biologically Active Materials

Abstract

An improved method for injection of chemicals into the squid giant axon is described. A large number of metabolically active materials were found to be without any effect upon the action potential. Tetraethylammonium chloride produced a striking prolongation of the action potential. Cocaine and ethanol caused a transient reduction in the amplitude of the action potential. A filter paper eluate was found to contain materials which caused repetitive firing followed by a reduction in amplitude of the action potential and finally inexcitability.