[Evolution of the astroglial reaction in the pyramidal pathway after injury of the rat motor cortex].

Investigation of astrocytes in the pyramidal tract of the rat 2 to 100 days after a lesion of the motor cortex indicates that the glial reaction, with increase in size of astrocytes and in affinity for Cajal's gold-sublimate, begins at the lesion and extends to the distal segments of the spinal cord. But this reaction recedes and disappears in lumbar and dorsal cord about 70 days after the operation. It persists in the cervical cord and in the brain. On the other hand, a characteristic increase in activity of glutamate andglucose-6-phosphate dehydrogenases is restricted to the vicinity of the lesion and does not even encroach upon the posterior limb of the internal capsule.