Experimental study of Vasculalized Nerve Allograft

Research Project

Project/Area Number	04670903
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	Orthopaedic surgery
Research Institution	Grant in Aid for scientific Research
Principal Investigator	TAMAI Susumu Nara Medical University, The Faculty of Medicine, Professor, 医学部, 教授 (10075088)
Co-Investigator(Kenkyū-buntansha)	YAJIMA Hiroshi Nara Medical University, The Faculty of Medicine, Research Associate, 医学部, 助手 (20221640)
Project Period (FY)	1992 – 1994
Project Status	Completed (Fiscal Year 1994)
Budget Amount *help	¥2,300,000 (Direct Cost: ¥2,300,000) Fiscal Year 1994: ¥400,000 (Direct Cost: ¥400,000) Fiscal Year 1993: ¥400,000 (Direct Cost: ¥400,000) Fiscal Year 1992: ¥1,500,000 (Direct Cost: ¥1,500,000)
Keywords	CAT activity / Nerve Allograft / Vascularized Nerve graft / FK506 / CAT活性 / 血管柄付神経移植 / 神経移植 / マイクロサージャリー / マイクロアンギオグラフィー
Research Abstract	Maintenance of favorable regeneration of transplanted peripheral nerves after discontinuation of immunosuppressant therapy was examined by means of allotransplantation of the sciatic nerve in rats. Brown-Norway rats (B-N : RT-1^n) were used as donors and Fisher rats (F344 : RT-1^1) were used as recipients. These two strains were MHC incompatible each other. Vascularized nerve grafts (VNG) and free nerve grafts (FNG) were compared. For immunosuppression, 0.5mg/kg of FK506 was intramuscularly injected once daily from the day of transplantion. On the basis of treatment with FK506,0 (no treatment), 4,6,8 and 12 week treatment groups were prepared. Each group consisted of 6 planted rats, and the animals were examined in the 16th and 20 weeks. Results were evaluated by choline acetyltransferase (CAT) activity, histological examination and electromyography. Axons continued to regenerate favorably after termination of treatment with the immunosuppressant. The myelin and schwann' s cells showed temporary rejection of the graft after the end of treatment with the immunosuppressant, but this change seemed to heal later. Administration of the immunosuppressant was necessary to continue until all the regenerating axons completed expension through the nerve graft. No significant differences were observed between the VNG and FNG.However, when the period of treatment with the immunosuppressant was short. CAT activity of VNG was higher than that of FNG.Hesurement of CAT activity was shown to be a simple method for the quantitative evaluation of axonal function.