NEURITIC GROWTH MAINTAINED NEAR THE LESION SITE LONG AFTER SPINAL-CORD TRANSECTION IN THE NEWBORN RAT

The spinal cord of neonatal and weanling rats was mid-thoracically transected. Either 3 or 6 mo. later the borders of the lesion site were studied by EM. No sign of axonal regeneration through the lesion site was found in either group, even though the glial reaction was minimal in neonatal operates. In both groups of operates, reactive axonal endings, presumed to result from the original surgery and neuritic growth were found in a reactive zone on both sides of the lesion site. Potential for axonal growth (regeneration or generation) is apparently maintained at the borders of the lesion in both groups of operates.