AbstractWe investigated the effects of bovine brain gangliosides on the neurotoxicity of vincristine in dissociated cultures of dorsal root ganglion cells from 10‐day chick embryos. The effects of the drugs were quantified as the numbers of neurite‐bearing cells or total neurite length in individual neurite‐bearing cells. The administration of vincristine (1 to 1000 pg/mL) inhibited neurite outgrowth from the cells, whereas gangliosides (10 to 1000 m̈g/mL) protected them against this inhibition in a concentration‐dependent manner. Electron microscopy revealed vincristine‐induced fragmentation and longitudinal disorientation of microtubules in neurites and showed the protection by gangliosides against such damaging effects. Our results show that exogenous administration of gangliosides attenuates the neurotoxicity of vincristine in vitro. © 1993 John Wile