MOSSY FIBER SPROUTING IN EPILEPTIC RATS IS ASSOCIATED WITH A TRANSIENT INCREASED EXPRESSION OF ALPHA-TUBULIN

Kainate-induced seizures lead to marked increases of alpha-tubulin mRN A and protein immunoreactivity in the rat dentate gyrus. The increase in alpha-tubulin mRNA was restricted to the granule cell bodies. Alpha -tubulin immunoreactivity was enhanced in granule cell dendrites and a xons (the mossy fibers), in the molecular layer. These changes peaked 6-12 days after kainate treatment and preceded the collateral sproutin g of mossy fibers which occur 12 to 30 days after seizures. The presen t results suggest that microtubule formation contributes to the synapt ic rearrangements which take place in the hippocampus after seizures.