INFLUENCE OF COLLAGEN AND LAMININ GELS CONCENTRATION ON NERVE REGENERATION AFTER RESECTION AND TUBE REPAIR

In order to assess the usefulness of collagen and laminin gels prefill ing nerve chambers to enhance nerve regeneration, we compared reinnerv ation of target organs after sciatic nerve resection leaving gaps of 4 or 6 mm followed by repair with silicone tubes in different groups of mice. Tubes were prefilled with saline solution, collagen gels, or la minin-containing gels at different concentrations. Functional reinnerv ation was assessed by noninvasive methods to quantitate recovery of sw eating, nociceptive, sensory, and motor functions in the hindpaw repea tedly during 4-5 months postoperation. The increase in gap length betw een nerve stumps delayed the beginning and reduced the degree of funct ional recovery achieved. Reinnervation started earlier and achieved sl ightly higher levels with collagen gel diluted at 1.28 mg/ml than with more concentrated (1.92 and 2.56 mg/ml) collagen gels and with saline -prefilled tubes bridging a 4-mm gap. Recovery was also better with di luted (4 mg/ml) than with concentrated (12 mg/ml) laminin-containing g el, although lower than with collagen gels and saline. By prefilling s ilicone tubes bridging a 6-mm gap, a length considered limiting for re generation in the mouse sciatic nerve, with diluted collagen or lamini n gels, both matrices allowed for higher levels of recovery and for su ccessful regeneration in a higher proportion of mice than saline solut ion. The laminin gel performed slightly better than the collagen gel. (C) 1998 Academic Press.