Objective To explore the neuroprotective effect and related mechanism of Zhenbao pill on rats with spinal cord injury.Methods A total of 60 SD rats were randomly divided into the control group,the model group and the Zhenbao pill group.Rats in the control group only exposed the spinal cord,and rats in the model group and the Zhenbao pill group established spinal cord injury models.After the model was successfully established,rats in the Zhenbao Pill group was given 0.6 g/kg Zhenbao pill orally once every 24 hours for 28 days,and rats in the control group and the model group were given the same dose of normal saline by gavage.Basso,Beattie,Bresnahan(BBB)score was used to evaluate the changes in motor behavior of rats in each group before and 4 weeks after intervention treatment.At the end of the experiment,the spinal cord tissue samples were collected,and the histopathological changes and apoptosis of nerve cells were observed and evaluated by HE staining and TUNEL staining.The expression of inflammatory factors TNF-α,IL-6 and IL-10 was detected by qRT-PCR.The expression of nuclear factor κB(NF-κB)/p65 pathway related proteins was detected by Western blot.Results After 4 weeks of intervention treatment,the BBB score of rats in the model group was lower than that in the control group,and the BBB score of rats in the Zhenbao pill group was higher than that in the model group,and the differences were statistically significant(P<0.05).The structure and morphology of spinal cord tissue of rats in the control group were normal;the spinal cord tissue structure of rats in the model group was disordered,with obvious bleeding,necrosis and edema,and a large number of inflammatory cells infiltrated;the degree of lesion of spinal cord tissue of rats in the Zhenbao pill group was significantly reduced than that in the model group.The number of apoptosis of spinal cord tissue in the Zhenbao pill group was decreased compared with that in the model group,and the difference was statistically significant(P<0.05).Compared with the control group,the expressions of TNF-α and IL-6 in spinal cord tissue in the model group were increased,while the expression of IL-10 was decreased,with statistically significant differences(P<0.05).Compared with the model group,the expressions of TNF-α and IL-6 in spinal cord tissue in the Zhenbao pill group were significantly decreased,while the expression of IL-10 was increased,with statistically significant differences(P<0.05).The protein expressions of NF-κB/p65 and p-NF-κB/p65 in spinal cord tissue of rats in the model group was up-regulated compared with those in the control group,and the differences were statistically significant(P<0.05);the protein expressions of NF-κB/p65 and p-NF-κB/p65 in spinal cord tissue of rats in the Zhenbao pill group were down-regulated compared with those in the model group,and the differences were statistically significant(P<0.05).Conclusion Zhenbao pill can effectively improve the behavioral symptoms of rats with spinal cord injury,alleviate its pathological changes,which has neuroprotective effects.Its mechanism may be related to blocking the NF-κB/p65 pathway and inhibiting the expression of inflammatory factors.