|Budget Amount *help
¥3,100,000 (Direct Cost : ¥3,100,000)
Fiscal Year 1999 : ¥100,000 (Direct Cost : ¥100,000)
Fiscal Year 1998 : ¥1,000,000 (Direct Cost : ¥1,000,000)
Fiscal Year 1997 : ¥2,000,000 (Direct Cost : ¥2,000,000)
Japanese monkey's ulnar nerve was harvested and cooled in stepwise manner with a computer-programmed freezer to -70℃ and preserved in liquid nitrogen at -196℃ after protection with 1.4 mol glycerin. After preservation, the nerve was rapidly thawed and washed in physiological saline to remove glycerin and morphological analysis was conducted. The nerve which was frozen rapidly showed collapse and destruction of myelin sheath. But the nerve frozen in a stepwise manner showed well-preserved structure of myelin sheath, partially collape and destructed. And the nerve frozen in a stepwise manner stored from 1week to 1year 5months at -196℃ in liquid nitrogen showed that myelin sheath was collapsed gradually, but more insignificant than rapid frozen nerve.
Next, Japanese monkey's ulnar nerve was severed and anastomosed as an interposition to another Japanese monkey.
In Group 1, ulnar nerve was grafted without any pretreatment (fresh allograft).
In Group 2, ulnar nerve cryopreserved was grafted (c
In Group 3, ulnar nerve was grafted immunosuppressed with Cyclosporin A (immunosuppressed fresh allograft).
Cyclosporin A was administered starting 4days preoperatively in a dose of 25mg/kg/day PO b.I.d. and postoperatively in a dose of 5mg/kg/day PO b.i.d during 4 months.
The ulnar nerve was exposed in the forearm 2cm proximal to the ulnar styloid and sharply divided. Then 1cm of a ulnar nerve was resected (deficit 1cm), and nerve graft was performed without tension by another Japanese monkey's ulnar nerve (lenth 3cm). Nerve graft was performed under an operating microscope with 8-0 nylon interrupted epineural sutures. 4 months after nerve graft, section from 1cm distal to the nerve graft and middle of the grafted nerve was removed. And fixed with glutaraldehyde and embedded with epon. Section 1 μm thick were stained with toluidine blue and examined with light microscopy. Light microswcopic examination demonstrated more axonal regeneration nerve numbers in Group 2 than Group 1 (less than Group 3). Morphological analysis was conducted to section from 1cm distal to the nerve graft and middle of the grafted nerve, and mean fiber diameter and % neural tissue were calculated. There was significant difference between Group 1, Group 2, and Group 3. Cryopreserved allograft appear to achieve more axonal regeneration than fresh allograft in Japanese monkey. But less axonal regeneration than immunosuppressed fresh allograft.
And the abductor digiti minimi, the first dorsal interosseous muscle was harvested and morphological analysis was conducted, there was no significant difference between Group 1, Group 2, and Group3. Less