The Influence Of NSAIDs On Spinal Cord Nerve Cells Apoptosis In Rats Induced By Chronic Compressive Nerve Root Injury

The Influence of NSAIDs on Spinal Cord Nerve Cells Apoptosis in Rats Induced by Chronic Compressive Nerve Root InjuryForewordThe role of apoptosis in the central nerve system injury was more and more emohasized.There come out a few literatures about peripheral nerve injury and cells in rats induced by chronic nerve root injury,and investigate the influences on it by the different types of NSAIDs,so trying to explain some atypical symptoms of the lumbar spinal stenosis syndrome,and also to provide some references fo the application of the NSAIDs in the spinal surgeries.Subjects and methods48 SD rats were arranged to four groups,they are Control group,Ligation group. Indometacin group,and Meloxicam group,and each group has 12 rats.In the Ligation group,the right L5 root of each rat was ligated loosely at the exit after right laminectoy, to create a chronic compressive model of the spinal nerve;evaluate the degree of spinal nerve injury after surgery;put the rats to death after 4 weeks,then the spinal cord segment was made into 5um slices connected with the L5 spinal nerve including the part 6mm to head and conus medullaris,these slices were dyed by HE and TUNEL method to mark the apoptosis cells and were investigated by the immunohistochemical method.This method was also applied in the Indometacin group and Meloxicam group, then the rats in this two group were fed by Indometacin and Meloxicam respectively after the surgery.In the Control group,the nerve roots were surrounded by the thread but not ligated at the exit,the reminder operations were the same as the ligation group.Results The rats appear nerve injury symptoms in different degrees in the Ligation, Indometacin and Meloxicam group about one week after sugery;the nerve injury scores in this three groups were not different(P>0.05);in the Ligation,there is apositive correlation between Apptotic Index and nerve injury scores(Spearman,2-tailed,0.01 level,r=0.0858,P<0.01).The results by TUNNEL dye appeared that a few positive cells were marked in the Ligation,distributing scope centralizes at the right side of the spinal cord connected L5 nerve root and its adjacent segment,there were also some positive cells marked dispersedly in the left side,and there was significant differences with the Control(P<0.01);a few positive cells were marked in the Indometacin and the Meloxicam group,there is no statistical difference with the Control(P>0.05),but there are significant differences between the two groups and the Ligation(P<0.01),and no statistical difference between the Indometacin group and Meloxicam group(P>0.05). On the immunohistochemical method,there is a little expression of the bcl-2 and Bax protein in the Control,a significant increasing expression of Bax protein and no expression of bcl-2 protein in the Ligation,a little expression of bcl-2 and Bax protein in the Indometacin and Meloxicam group.ConclusionThe chronic compressive injury of the nerve root can result in spinal anterior angle moto neurons apoptosis of this spinal cord segment connected to the nerve root,and there was a positive correlation with the injury degrees;the possible mechanisms is that the living signals and nutritions of the central nerval cells lost because of the chronic pression injuries,and triggered the cell processional death.Nonselective COX inhibitor-Indometacin and selective COX-2 inhibitor-Meloxicam both can prevent the spinal nerve cells from apoptosis.The results indicated that the mechanisms of inhibiting nerve cells apoptosis by NSAIDs are independent to the isoforms of COX; and NSAIDs didn't improve nerve injury symptoms of the rats.