Apparent anterograde transport of basic fibroblast growth factor in the rat nigrostriatal dopamine system

Five hours after the stereotaxic injection of approximately 1 ng of [125I]basic fibroblast growth factor (bFGF) into rat substantia nigra (SN), small but consistent amounts of radioactivity were found in the ipsilateral striatum (CP). None was found in the ipsilateral thalamus or contralateral CP, SN or thalamus. The amount found in the ipsilateral CP was very markedly reduced in rats injected 5-7 days after 6-hydroxydopamine-induced lesions of the nigrostriatal dopaminergic tract but was unaffected by prior kainic acid lesion of the CP. No radioactivity was found in the ipsilateral SN 5 h after injections of similar amounts of radioactive bFGF into the CP. These results are consistent with anterograde transport of bFGF in the dopaminergic nigrostriatal tract.