The study of morphology of cerebellar fastigial nuclei-hypothalamic fibers

Objective:To study the neural pathway connection between the cerebellar fastigial nuclei(FN) and the hypotha-lamus.Methods:Biotinylated dextran amine(BDA) was infused into one side of cerebellar FN and 8 days later,the routes and ending locations of the projections from cerebellar FN neurons to hypothalamus were observed.A technology of electrolytic lesion was used to destroy the projections of cerebellar FN neurons to hypothalamus in decussation of superior cerebellar pe-duncle(xscp).Results:Subsequent to an injection of BDA into unilateral FN,FN-hypothalamic projections passed through the superior cerebellar peduncle,crossed in its decussation and then entered the hypothalamus.These fibres were terminated pri-marily in lateral hypothalamic area.On the eighth day after electrolytic lesion of the fibres in xscp,the FN-hypothalamic pro-jections were damaged and there were no visible BDA-positive endings in hypothalamus.Conclusion:The cerebellar FN neu-rons may project directly to the hypothalamus through the xscp,which probably is the pathway mediating the modulation of certain functions by the cerebellum.