Objective： To assess the effect of cyclosporine A （CsA） loaded in chitosan conduit on bridg- ing the sciatic nerve defects in a rat model. Methods： A 10 mm sciatic nerve defect was bridged using a chitosan condui...Objective： To assess the effect of cyclosporine A （CsA） loaded in chitosan conduit on bridg- ing the sciatic nerve defects in a rat model. Methods： A 10 mm sciatic nerve defect was bridged using a chitosan conduit filled with 10 μl carrier-drug dilu- tion （10 pg/L CsA）. In control group, the conduit was filled with the same volume of carrier dilution alone. The regene- rated fibers were studied 4, 8 and 12 weeks after surgery. Results： The functional study confirmed faster recov- ery of the regenerated axons in treatment group than control group （P〈0.05）. There was statistically significant differ- ence of the gastrocnemius muscle weight ratios between treatment and control groups （P〈0.05）. Morphometric indi-ces of regenerated fibers showed that the number and diam- eter of the myelinated fibers in CsA-treated animals were significantly higher than those in control group. In immunohistochemistry, the location of reactions to S-100 in CsA group was clearly more positive than control group. Conclusion： CsA loaded in a chitosan conduit results in improvement of functional recovery and quantitative mor- phometric indices of sciatic nerve. It is easily available with- out any complications compared with its systemic administration.展开更多
Objective：To evaluate the local effect of vascular endothelial growth factor （VEGF） on transected sciatic nerve regeneration.Methods：Sixty male white Wistar rats were divided into four experimental groups randomly...Objective：To evaluate the local effect of vascular endothelial growth factor （VEGF） on transected sciatic nerve regeneration.Methods：Sixty male white Wistar rats were divided into four experimental groups randomly （n=15）.In transected group the left sciatic nerve was transected and the stump was fixed to adjacent muscle.In treatment group the defect was bridged using a silicone graft filled with 10μL VEGF.In silicone group the graft was filled with phosphate-buffered saline.In sham-operated group the sciatic nerve was exposed and manipulated.Each group was subdivided into three subgroups with five animals in each and nerve fibers were studied 4,8 and 12 weeks after operation.Results：Behavioral test,functional study of sciatic nerve,gastrocnemius muscle mass and morphometric indices confirmed a faster recovery of regenerated axons in VEGF group than in silicone group （P〈0.05）.In immunohistochemical assessment,reactions to S-100 in VEGF group were more positive than that in silicone group.Conclusion：Local administration of VEGF will improve functional recovery and morphometric indices of sciatic nerve.展开更多
Objective: To investigate the expression of neurotrophin-3 (NT-3) gene in Schwann cells of rat sciatic nerve introduced by an adenovirus vector in vivo. Methods: A recombinant adenovirus vector for NT-3 (Ad-NT-3) was ...Objective: To investigate the expression of neurotrophin-3 (NT-3) gene in Schwann cells of rat sciatic nerve introduced by an adenovirus vector in vivo. Methods: A recombinant adenovirus vector for NT-3 (Ad-NT-3) was propagated in 293 packaging cells and titered with tissue culture infectious dose 50 (TCID 50). Ad-NT-3 was injected directly into the rat sciatic nerve after transection and immediate repair. Immunohistochemical staining was employed to determine the expression of NT-3 in Schwann cells in rat sciatic nerve and the expressive intensity of the tissue slices of the sciatic nerve was measured with LEICA M550 image analysis system. Results: On the 2nd day after injection of Ad-NT-3, positive stain in the Schwann cells was apparent in the vicinity of anastomosis. NT-3 expression increased significantly on the 7th day (P< 0.01) and then decreased 14-28 days after injection (P< 0.01). There was no significant difference of NT-3 expression between the 14th and 28th day groups (P> 0.05). Compared with the 2nd day group, the 14th and 28th day groups still maintained a relatively high level of NT-3 (P< 0.01). Intact and repaired nerves, which were injected with adenovirus encoding LacZ genes ( Ad-LacZ) or physiological saline served as controls, showed no NT-3-positive Schwann cells. Conclusions: An adenovirus vector can be used to induce efficiently the expression of NT-3 gene in Schwann cells of rat peripheral nerves following nerve injury and repair, which suggests that neurotrophic factors can be introduced into Schwann cells with an adenovirus vector to promote peripheral nerve regeneration.展开更多
文摘Objective： To assess the effect of cyclosporine A （CsA） loaded in chitosan conduit on bridg- ing the sciatic nerve defects in a rat model. Methods： A 10 mm sciatic nerve defect was bridged using a chitosan conduit filled with 10 μl carrier-drug dilu- tion （10 pg/L CsA）. In control group, the conduit was filled with the same volume of carrier dilution alone. The regene- rated fibers were studied 4, 8 and 12 weeks after surgery. Results： The functional study confirmed faster recov- ery of the regenerated axons in treatment group than control group （P〈0.05）. There was statistically significant differ- ence of the gastrocnemius muscle weight ratios between treatment and control groups （P〈0.05）. Morphometric indi-ces of regenerated fibers showed that the number and diam- eter of the myelinated fibers in CsA-treated animals were significantly higher than those in control group. In immunohistochemistry, the location of reactions to S-100 in CsA group was clearly more positive than control group. Conclusion： CsA loaded in a chitosan conduit results in improvement of functional recovery and quantitative mor- phometric indices of sciatic nerve. It is easily available with- out any complications compared with its systemic administration.
文摘Objective：To evaluate the local effect of vascular endothelial growth factor （VEGF） on transected sciatic nerve regeneration.Methods：Sixty male white Wistar rats were divided into four experimental groups randomly （n=15）.In transected group the left sciatic nerve was transected and the stump was fixed to adjacent muscle.In treatment group the defect was bridged using a silicone graft filled with 10μL VEGF.In silicone group the graft was filled with phosphate-buffered saline.In sham-operated group the sciatic nerve was exposed and manipulated.Each group was subdivided into three subgroups with five animals in each and nerve fibers were studied 4,8 and 12 weeks after operation.Results：Behavioral test,functional study of sciatic nerve,gastrocnemius muscle mass and morphometric indices confirmed a faster recovery of regenerated axons in VEGF group than in silicone group （P〈0.05）.In immunohistochemical assessment,reactions to S-100 in VEGF group were more positive than that in silicone group.Conclusion：Local administration of VEGF will improve functional recovery and morphometric indices of sciatic nerve.
文摘Objective: To investigate the expression of neurotrophin-3 (NT-3) gene in Schwann cells of rat sciatic nerve introduced by an adenovirus vector in vivo. Methods: A recombinant adenovirus vector for NT-3 (Ad-NT-3) was propagated in 293 packaging cells and titered with tissue culture infectious dose 50 (TCID 50). Ad-NT-3 was injected directly into the rat sciatic nerve after transection and immediate repair. Immunohistochemical staining was employed to determine the expression of NT-3 in Schwann cells in rat sciatic nerve and the expressive intensity of the tissue slices of the sciatic nerve was measured with LEICA M550 image analysis system. Results: On the 2nd day after injection of Ad-NT-3, positive stain in the Schwann cells was apparent in the vicinity of anastomosis. NT-3 expression increased significantly on the 7th day (P< 0.01) and then decreased 14-28 days after injection (P< 0.01). There was no significant difference of NT-3 expression between the 14th and 28th day groups (P> 0.05). Compared with the 2nd day group, the 14th and 28th day groups still maintained a relatively high level of NT-3 (P< 0.01). Intact and repaired nerves, which were injected with adenovirus encoding LacZ genes ( Ad-LacZ) or physiological saline served as controls, showed no NT-3-positive Schwann cells. Conclusions: An adenovirus vector can be used to induce efficiently the expression of NT-3 gene in Schwann cells of rat peripheral nerves following nerve injury and repair, which suggests that neurotrophic factors can be introduced into Schwann cells with an adenovirus vector to promote peripheral nerve regeneration.
