[Plastic synaptic reorganization in the sensorimotor cortex of adult cats after destruction of the contralateral nucleus intermedius of the cerebellum].

Using the intracellular microelectrode technique the reactions were investigated in corticospinal neurons (CSN) after stimulation of contralateral (cIP) and ipsilateral interpositus nucleus of cerebellum as well as ventrolateral nucleus of thalamus. Experiments were made on adult intact cats and the same preliminary lesion of cIP nucleus (exposition from 1 to 6 months). Acceleration of the monosynaptic thalamo-cortical EPSPs time to peak in slow CSN was revealed in operated animals. It indicated that there was remote terminal dendrosomatic sprouting and formation of new synapses on proximal segments of SD-membrane of CSN. This made it possible to suppose that there was formed ipsilateral interposito-thalamocortical way which duplicated the same contralateral in intact animals. The contralateral cortico-interposital collaterals in intact and the analogic ipsilateral sprouting in operated animals have been shown.