Effects of anisatin on the GABA action in the crayfish neuromuscular junction

Anisatin depressed the conductance increase produced by GABA in a non-competitive manner and decreased the amplitude of the inhibitory junctional potentials. The presynaptic inhibition was depressed by anisatin in the similar concentrations to those of picrotoxin. The blockade of the presynaptic inhibition by anisatin was irreversible, whereas the effect of anisatin on postsynaptic inhibition subsided after prolonged washing of the preparation.