LACK OF REGENERATION IN SPINAL CORD OF RAT

Abstract

Sugar and Gerard ([image]40) reported sufficient regeneration, after transection, in the spinal cord of 3- to 5-week-old albino rats to enable them to demonstrate histologically the continuity of neurons across the scar tissue in the transected cord and to give the animal functional use of its hind limbs. An attempt has been made to repeat these expts. with rats of 19 days and older. If the cord has been clearly and demonstrably severed insufficient regeneration occurs to cross the gap. Grafts of sciatic nerve were placed in the gap in some animals but this did not help. A cuff of tantalum foil was placed around the ends of the cut cord, but this did not prevent connective tissue invasion. Reflexes of the isolated caudal cord were present,and at times these simulated coordinated walking. Histological sections showed fibers invading the scar and the transplants but not crossing to the other cut end of the cord. The findings of extensive regeneration in the spinal cord of rats by Sugar and Gerard were not confirmed.