Effects of Fresh and Degenerated Autogenous Nerve Graft in Segmental Defect of Sciatic Nerve of Rabbit

Park, Jong Beom; Lee, Moon Hong; Rhee, Seung Koo

Abstract

The potential for nerve regeneration and recovery of its function exists in the presence of a suitable pathway for regenerating axon and endoneurial tube can serve as nerve conduit for regenerating axon in fresh nerve graft. But value of degenerated nerve as donor nerve has not been established till now. This experiment assessed the chronologic influence of fresh and degenerated nerve graft on axonal growth for 10mm gap of sciatic nerve in rabbit and how long degenerated nerve was ahle to serve as a nerve conduit microscopically. Electromicroscopically, the regenerating axons which were ohserved in the degenerated nerve graft had more abundant unmyelinated fibers and revealed abundant collagen fibers in the endoneurium. And these regenerating axons became gradually surrounded with newly developed basal lamina and decreased the collagen fibers at l2 week of degenerated nerve graft. Histologically, myelinated axons which were observed in central area of the degenerated nerve graft at 8 week of degenerated nerve graft were relatively thinner, but a definite structural difference of regenerating axons was not found except reduction of number compared with those of tresh nerve graft. The numher of myelinated axons was 6,072+/-l42 in normal sciatic nerve, 4,479+/- 157 in fresh nerve graft group, and 2,968+/-168 in the degenerated nerve graft group. Difference of the number of myelinated axons between fresh and degenerated nerve graft group was significant stati stically(P<0.05). These results showed that the ability of a degenerated nerve graft as a passage for the regenerating axons and it can be employed as one of the favorable nerve conduits.