Objective:To investigate the protective effect of Calpain inhibitor E-64-D on nerve function after rat spinal cord injury.Methods:Rats spinal cord injury model was prepared by Allen’s method. The successful models of rats with spinal cord injury were randomly divided into injury group(n=24)and intervention group(n=24). Another 10 normal rats were selected as the control group

and only received sham surgery. Spinal cord injury intervention group were given E-64-D by intravenous injection in the post-operation. Rat spinal cord calpain-1 m RNA levels and hindlimb function were detected and evaluated on the 1

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14 d and 28 d(n=6 at each time point)after operation. Rat tissues of spinal cord were evaluated by HE and Nissl staining. Results:There was no significant difference in Calpain-1 m RNA levels of control group at different time points

while differences existed between spinal cord injury group and spinal cord injury intervention group at different time points(P<0.05). On 28 d

Calpain-1 m RNA expression level of the spinal cord injury intervention group and control group had no significant difference(P>0.05). Tarlov score and inclined plane test results between pinal cord injury group and spinal cord injury intervention group had significant differences on the postoperative 7

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28 d(P<0.05). Motor function of spinal cord injury intervention group was better than that of spinal cord injury group. Neurons form and quantity of spinal cord injury intervention group were better than those of spinal cord injury group. Conclusion:Inhibiting Calpain after spinal cord injury can prevent neuronal apoptosis and necrosis

and promote the recovery of spinal cord function.