Treatment of Lumbar Intervertebral Disc Herniation with Erythropoietin in a Rat Model

Objective To establish a rat animals model of lumbar intervertebral disc herniation,and to explore the curative effect of the erythropoietin on lumbar intervertebral disc herniation.Methods Thirty SD rats were randomly divided into experiment group(n=18)and control group(n=12).For the disc herniation model,autologous nucleus pulposus was applied to L4,L5 nerve roots.In the experiment group,incisions were sutured after gelatin sponge containing erythropoietin was fixed next to the nerve roots.The control rats only received incision suturing.After successful establishment of the model,rats in experiment group and control group were intraperitoneally injected with erythropoietin(5 000 U·kg-1) and normal saline(1 mL)once per day,respectively.At 12,24,36,48,72 and 96 hours after operation,3 rats in experiment group and 2 in control group were sacrificed to take nerves and surrounding tissues for TUNEL staining and TNF-α positive cell counting.Results The apoptosis rate of spinal nerve cells at 24,48,72 and 96 hours after operation and the number of TNF-α positive cells at 12,24,36 and 48 hours after operation in experiment group were significantly lower than those in control group(all P0.05).Conclusion The erythropoietin can effectively inhibit nerve cell apoptosis and TNF-α expression in lumbar intervertebral disc herniation animals model.