Tetanus toxin affects the K+-stimulated release of catecholamines from nerve growth factor-treated PC12 cells

Tetanus toxin specifically binds to neuronal surfaces and interferes with the release of transmitters. The effect of tetanus toxin pretreatment of PC12 cell line, taken as a model of neuronal cells in culture, was studied and found that it depresses depolarization-dependent catecholamines secretion. This effect is limited to PC12 cells fully differentiated by the action of Nerve Growth Factor (NGF) and is indicative of the expression of specific binding sites for tetanus toxin during transition from the undifferentiated state. Specific binding of [125I] tetanus toxin to NGF-treated PC12 was demonstrable. The toxin has no effect on the 45Ca accumulation coupled with the depolarization dependent release of catecholamines.