Effect of explosive decompression on neural function of rats with the spinal cord injury

Abstract

Objective To investigate the effect of explosive decompression on the neural function of rats with the spinal cord injury.Methods Thirty-two male healthy Sprague-Dawley rats were randomly divided into 4 groups:the control group (group 1),the simple acute spinal cord injury group (group 2),the simple explosive decompression group (group 3),and the explosive decompression combined with acute spinal cord injury group (group 4),each consisting of 8 rats.Then,the animal model of explosive decompression combined with acute spinal cord injury was developed.Evaluation of neural performance was made and walking gait losing experiment (WGLE) was performed in the rats with spinal cord injury.Results Similar to the rats in group 1,scores of Basso-Beattle Bresnahan Locomotor Rating Scale (BBB score) for the rats in group 2 were on the average(21),while BBB scores for group 2 and group 4 were obviously lower(0.67 ± 0.82,0.33 ±0.52),following injury,and slow recovery was seen in them,with the animals in group 2 being recovered obviously faster.After 4 weeks,no statistical significance could be noted in the BBB scores(17.00 ± 1.41)for the animals in group 2 and group 4,when compared with those of the control group (21) (P ＞ 0.05).However,sensory and motor functions and reflex of the animals in group 4 recovered more slowly,when compared with those of group 2.Significant differences could still be seen,6 weeks after injury,when compared with the animals of groups 1,2 and 3 (P ＜0.05).The animals of group 1 and group 3 made no mistakes in WGLE,while the rats in group 2 and group4 had a relatively higher walking gait losing times(15.33 ± 0.63,15.58 ±0.49),and statistical significance could also be noted,when compared with the control group (P ＜ 0.01).Then,the animals gradually recovered,with the animals of group 4 recovered more slowly.Six weeks after injury,the animals of group 4 had on the average walking gait losing times (8.17 ± 0.56),and statistical significance could be seen in them,when they were compared with those of groups 1,2 and 3 (P ＜ 0.01 or P ＜0.05).Conclusions Explosive decompression could induce spinal cord injury,which would remain for a long time,indicating that explosive decompression might bring further injury to the neural function of rats. Key words: Rats; Explosive decompression; Spinal cord injury; Combined injury