In the present study, we used genipin-crosslinked gelatin conduit (GGC) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide / N-hydroxysuccinimide cross-linked gelatin conduit (ENG) to bridge a 10 mm gap in the sciatic nerve of the Sprague-Dawley rat. These two biodegradable materials are both successful apparatus to reconstruct nerve gaps, and can avoid the disadvantage of a second surgery. However, the regenerated nerve in GGC and ENG were less mature than the regenerated nerve in non-biodegradable silicone tube. Moreover, the scar tissue at the outer area of the regenerated nerve caused by degrading materials could have harmful effect to the regenerating nerve.
In this study, we compared the effectiveness of three conduit materials, named silicone, GGC and ENG, in repairing a 10 mm gap in the rat sciatic nerve. Eight weeks after implantation, their effectiveness as a guidance channel were evaluated by morphometric data and protein analysis of the regenerated nerve.
As a result, we found that the regenerated nerves in the silicone conduits had the most mature structure, whereas the regenerated nerves in the GGC conduits were the most immature one. In addition, the higher expression of nerve regenerating associate protein synapsin and GAP43 in silicone group also indicated that the regenerating process in silicone conduits were more vigorous. On the other hand, the level of scar formation associated protein TGF-β1 was lower in the silicone group than the other two groups, which suggested the harmful effect of scar tissue in nerve regeneration.
