EARLY CEREBELLAR HEMISPHERECTOMY IN THE RAT - EFFECTS ON THE MATURATION OF 2 HINDLIMB MUSCLES AND ON LUMBAR MOTONEURONS

Cerebellar hemispherectomy before the 10th day in rats leads to extens ive neuronal remodelling. In the present study the problem was studied whether such early lesions also have effects on the maturation of the soleus and the extensor digitorum longus muscles in the hindleg as we ll as on the formation of dendrite bundles from motoneurons innervatin g the soleus muscle. Results indicate consistent left-to-right differe nces in the numbers of muscle fibres but no differences in muscle diff erentiation. Dendritic bundles of soleus motoneurons, at the side ipsi lateral to the cerebellar lesion are absent or less conspicuous in com parison to the contralateral side or to those bundles in normal rats. Cerebellar lesioning at the 30th day does not affect dendritic bundles .