ELECTRON-MICROSCOPIC EVIDENCE OF SYNAPTIC REORGANIZATION IN THE CONTRALATERAL MOTOR CORTEX OF ADULT-RATS FOLLOWING FACIAL-NERVE LESION

Here we report on the rapid changes in the motor cortex of the rat fol lowing peripheral lesioning of a motor nerve. Facial nerve transection increases synaptic reorganization (autophagy, lysosomal degradation o f synaptic components) already within 4 h after lesion. These changes occur in the motor cortex of both hemispheres, i.e. on the same and co ntralateral sides. An increase in the number of presynaptic lysosomes was transient and returned to below normal values within 24 h after fa cial nerve transection.