[Effect of tetanus toxin and colchicine on synaptic membranes of rat cerebral cortex]

It was shown that purified tetanus toxin did not influence the activity of the Na, K-ATP-ase fractions of the synaptic membranes of the rat cerebral cortex, it had no effect on the inhibition of Na, K,-ATP-ase under electrical stimulation of the synaptic membrane suspension, or the GABA--3H binding by the synaptosomes in vitro. Tetanus toxin (400--4000 DLM) and colchicine (1 mM) induced a decrease of osmotic sensitivity of the nerve endings. Colchicine in low concentrations (10(-5)-10(-3) M) failed to influence Mg-and Na, K-ATP-ases, but considerably inhibited both ATP-ases at higher concentrations.