Abstract: The experiment is to trace the projection from the central cervical nucleus(CCN)to the cerebellum in the rabbits with the method of autoradiography anterogradely.Injections of ³H-leucine were made into the region of the CCN in the C₂ segment of the spinal cord in 6 rabbits.Observations were made on the labelled fibers and the terminal distributions within the cerebellum after autoradiographic procedures. In the cerebellum,labelled mossy fiber terminals were found bilaterally but a more proportion in the side contralateral to the injection site,concentrated from lobuleⅠtoⅣand longitudinal distribution paralelled to the midline and also in average from the depth to the superficial parts of the different folia.In addition,a less number of terminals were found in the lobules Ⅷ_b,Ⅸ_a of the vermis zone and paramedian lobe.The labelled silver grains were also found in the brainstem and cerebellar superior peduncle on the contralateral side. The findings suggest that the fibers of CCN in the rabbits project to the cerebellum directly.The result implies that the CCNmay convey the input from the skin of the neck region and proprioceptive input from tendons,ligaments and joints.

Key words: central cervical nucleus, cerebellar projection, aytoradiography, rabbit