Effects Of Cyclosporine-A Immunosupression On Allograft Nerve Regeneration

[Objective] To study on the peripheral nerve regeneration through allografts immunosupressed with cyclosporine-A(CSA).[Methods] Therty-two rats were equally divided into two groups at random. The rats in group A were riot given any immunosupression while in group B immunosupressed with cyclosporine A. In each animal, bilateral sciatic nerve defects as 10mm long was made, the left sciatic nerve was bridged with fresh nerve allograft and the right side with nerve allograft frozen in liquid nitrogen(-196C)..Eight weeks after operation, -the action potential latency (APL),axonal count (AC) and the tibial anterior muscular wet weight(WW) of each rat were measured .The data were, analyzed with SAS processing system by t-test, and the significant level was P<0.05 .[Results]1,The results of the action potential latency (APL), axonal count(AC) and the tibial anterior muscular wet weight(WW) were as follow. The results of the left in group A( group AL) were APL7. 726+ 0. 445 ,AC47. 5+12. 73 and WW0.226+0.0585; and that of the right in group A (group AR) were APIP 3. 124+0. 713, AC 111.5+ 20.89 and WW 0.3341+0.0680 ,and APL 3.10 + 0.325 , AC251 + 19. 54 , WWO. 3211 + 0. 0458 in the left of group B (group BL), and APL 3. 138 + 0. 324 , AC200.5+17. 16, WW 0. 3117 + 0. 0360in the right of group B (group BR) .Among these groups, the results in group AL of the action potential latency (APL) was the longest and of axonal count (AC) and the tibial anterior muscular wet weight (WW) were the lest (P<0. 01) . Thus demonstrated the nerve regeneration of fresh allograft was the most poor among these groups. The average APL of group BL was more than that of other group (P<0. 01) . Thus revealed that the nerve regeneration of fresh allograft under immunosupression with CSA was the best among these groups. In group BR with more AC(P<0.01) ,the nerve regeneration of frozen nerve allograft under immunosupression with CSA was better than that of group AR.2, Optical microscope observation the muscular state can be observed by magnifing it 梠perated after 8 weeks, the muscular fiber of group AL appeared relatively wide-ranging degeneration and atrophy, while in group AR part of it dagenerated and atrophy; it in group BL degenerated lightly and atrophied not obviously, but in group BR it degenerated and atrophied lightly. The middle nerve HE staining were observed as followed: in group AL both had relatively general lymphocytic infiltration and focal lymphocytic infiltration , group AR had a little lymphocytic infiltration; the nerve boundles were intact both in group BL and BR , there are more regenaration blood vessels can be observed in group BL than that in group BR.[Conclusions] (1)The nerve regeneration through fresh allograft without inmmuosppresion was the most poor among these groups because the fresh nervehad strongest antigenicity.(2)The antigenicity of frozen nerve was weaker so its regeneration was better. Furthermore, the regeneration ability was improved by immunosupression. (3) Under immunosupression with cyclosporine-A , the fresh nerve allograft was covered with intac Shwann cells and myelin sheath and more easily to create blood vessels , so the nerve regeneration ability was improved.Above all, the immunosupression with cyclosporine-A was helpful to suppress the rejection of nerve allograft and to improve the peripheral nerve regeneration.. Wang jun (Orthopaedics)Directed by Li shu zhong Sun lei...