Remote Effects from Cerebellar Lesion to Contralateral Cerebrum

The purpose of this study was to investigate the remote effects from cerebellar lesion to the contralateral cerebrum. Left cerebellar hemispheres of male Wistar rats were resected under an operative microscope. Seven days,-30days, and 60days after the left cerebellectomy, blood flows in the cerebral cortex (frontal, parietal, occipital) , the thalamus (ventral posterior nucleus and ventral posterolateral nucleus) , and the globus pallidus (n=6 per group) were measured. We also studied blood flows of sham operated group at same place and period (n=6). The values of the blood flow in the right cerebral cortex and thalamus were significantly lower than those of the left sides at 7days after cerebellar hemispherectomy. At 60days after cerebellar hemispherectomy, no lateralities of blood flow were observed. No lateralities were observed in the globus pallidus at any days. At 7days after the cerebellar hemispherectomy, the CO_2 reactivities of cerebral blood flow were studied under various PaCO_2 levels(n=6 for cerebellar hemispherectomy group, n=6 for sham operated group). Vasoconstrictive response for hypocapnea was less in the area with diaschisis, but vasodilative response was more in the area with diaschisis. It is concluded that the blood flow in the cerebral hemisphere is reduced by the contralateral cerebellar hemispherectomy, then gradually recovered. Reactivities of CBFs against changes in PaCO_2 suggest that cerebral vessels might be constricted in the area with diaschisis.

小脳病変

遠隔効果(diaschisis)

能循環

脳血管反応性