Experimental study of erythropoietin on promoting sciatic nerve regeneration in rats

Abstract

Objective To explore the effect of erythropoietin (EPO) on nerve regeneration after sciatic nerve injury and repair in rats and provide experimental basis for clinical treatment of peripheral nerve injury.Methods Forty male Sprague-Dawley rats were randomly divided into two groups, which were named EPO group and NGF group respectively . The sciatic nerve with 10 mm defect was bridged with silicone conduit. Rats of EPO group and NGF group received injection of erythropoietin and nerve growth factor respectively. At 4 and 8 weeks postoperatively, 10 rats from each group were subject to sciatic functional index (SFI), motor nerve conduction velocity (MNCV) and histomorphometric evaluation and immunohistochemical staining of protein gene product 9. 5 (PGP 9. 5) to assess the effect of erythropoietin on rat sciatic nerve regeneration. Results Four weeks after the operation , SFI was - 78.85 + 3.87 in EPO group and - 79.98 ± 4.58 in NGF group. There was no significant difference between the two groups( P > 0.05). Eight weeks postoperatively , SFI was - 60.26±2.91 in EPO group and -64.65 ± 4.11 in NGF group, with significant difference between the two groups( P <0.05). Four and eight weeks after the operation, MNCV, the number of myelinated nerve fibers, the mean optical density and the integration optical, density of PGP 9.5-immtive nerve fibers were significantly higher in EPO group than in NGF group (P < O. 05). Conclusion Erythropoietin can improve nerve regeneration after sciatic nerve injury and repair in rats. Key words: Sciatic nerve; Injuries; Nerve regeneration; Etythropoietin