DIFFERENTIAL-EFFECTS OF MICROTUBULE INHIBITORS ON AXONAL BRANCHING AND ELONGATION OF CULTURED RAT HIPPOCAMPAL-NEURONS

We investigated the effects of microtubule inhibitors, taxol and colch icine, on the axonal branching and elongation in cultured rat hippocam pal neurons. Taxol (50 nM) did not affect the morphology of neurons cu ltured under the control conditions, but significantly reduced the axo nal branching stimulated by basic fibroblast growth factor. The axonal elongation stimulated by astrocyte-conditioned medium was not affecte d by the same concentration of taxol. Colchicine (10 nM) showed simila r effects as taxol. These results suggest that microtubules play more important roles in axonal branching than in axonal elongation.