The 2003 Annual Meeting of OASYS_NEW

Not yet assigned to a slot - 12:48 AM

In Vivo Effect of Ngf-7s on Motor Neuronal Regeneration through Nerve and Vein Grafts

Gravvanis A, Lykoudis E, Tagaris G, Papalois A, Panayotou P, and Ioannovich I. Department of Plastic Surgery, Microsurgery and Burns Center General Hospital of Athens "G. Gennimatas", Athens, Greece

Purpose: The aim of this study was to investigate the effect of local administration of Nerve Growth Factor-7S (NGF-7S) on the axonal regrowth of mixed peripheral nerves through nerve or inside-out vein grafts. Materials and methods: One hundred and twenty male Wistar rats were randomised in four groups of thirty animals each. A defect, 12 mm long in the right sciatic nerve, was inflicted and repaired either with a nerve autograft (group A and B) or an inside-out vein graft (group C and D). NGF-7S (group A and C) or normal saline (group B and D, control groups) was locally administered daily during the first 3 weeks. For this purpose, a subcutaneously implanted reservoir connected to a silicone tube was used. Electrophysiologic and histologic - morphometric studies were carried out at 4, 6, 8, 10 and 12 weeks post-operatively (subgroups a, b, c, d and e, respectively, n=6 each). Results: Histologic appearance of cross sections was better in the NGF groups, with better axonal orientation and distribution. Analysis of variance and linear regression analysis showed that NGF consistently provided a significant increase in the average number, the myelin thickness, and the diameter of myelinated axons throughout the course of time (group A vs. B and group C vs. D). Most importantly, electrophysiologic findings verified the beneficial effect of NGF on motoneuronal regeneration, since the recovery of the compound muscle action potential was faster in the NGF treated-groups and reached the normal value at 8 (group A) and at 6 (group C) weeks. Conclusion: According to these findings, there is a strong evidence of the beneficial effect of NGF-7S on peripheral nerve regeneration through nerve and inside-out vein grafts.