Attenuation of inhibitory processes in the central nervous system by tetanus toxin: an in vitro study on rat hippocampal slices.

The influence of tetanus toxin on the efficiency of recurrent inhibition in the rat hippocampal slice was tested. The efficiency of the recurrent inhibition diminished in a dose-dependent manner following incubation of the slices with tetanus toxin. The effect was not observed in the slices preincubated for 3 hours with neuraminidase from Vibrio cholerae. This treatment reduces markedly the level of polysialogangliosides (receptor for tetanus toxin). It is concluded that tetanus toxin influences the efficiency of some inhibitory synapses in the central nervous system and that a certain level of polysialogangliosides is necessary for tetanus toxin to exert its action.