[Experimental research on revascularization of chemically extracted acellular allogenous nerve graft].

OBJECTIVE

To observe the revascularization process of chemically extracted acellular allogenous nerve graft in repairing rat sciatic nerve defect.

METHODS

Eighty adult male SD rats were selected. The sciatic nerve trunks from ischial tuberosity to the ramus of tibiofibular nerve of 16 SD rats were obtained and were prepared into acellular nerve stents by chemical reagent. Sixty-four SD rats were used to prepare the models of sciatic nerve defect (1.0 cm) and thereafter were randomized into two groups (n=32): experimental group in which acellular allogenous nerve grafts were adopted and control group in which orthotopic transplantation of autologous nerve grafts were adopted. Postoperatively, the general conditions of all rats were observed, and the gross and ALP staining observation were conducted at 5, 7, 10, 14, 21, 28 days and 2, 3 months, respectively.

RESULTS

All the incisions were healed by first intention. Trailing status and toe's dysfunction in extension happened to the right hindlimb of rats in two groups and were improved 6 weeks after operation. General observation showed that the grafts of two groups connected well to the nerves, with appearances similar to that of normal nerve. ALP staining demonstrated that the experimental group had no ingrowth of microvessel but the control group had ingrowth of microvessel 5 days after operation; the experimental group had ingrowth of microvessel but both groups had no microvessel 7 days after operation; few longitudinal microvessel throughout the grafts were observed in both groups 10, 14 and 21 days after operation; no obvious difference in capillary network of grafts was observed between two groups 28 days after operation; and the microvascular architecture of grafts in both groups were similar to that of normal nerve 2 and 3 months after operation.

CONCLUSION

When the chemically extracted allogenous nerve graft is adopted to repair the peripheral nerve defect, new blood microvessels can grow into grafts timely and effectively.