Correlation between Expression of Inducible Nitric Oxide Synthase and Neural Cell Apoptosis after Chronic Compression of Cauda Equina Nerve in Rats / 中国医科大学学报

ABSTRACT

Objective To study the relationship between the expression of inducible nitric oxide synthase(iNOS)and neural cell apoptosis after chronic cauda equina compression. Methods Totally 30 male adult SD rats were randomly divided into 2 groups as the control group and the experi?mental group. The control group received sham operation with single laminectomy of L5 lumina. In the experimental group,the silicon sheet was in?serted into the spinal canal of L4 to cause single level compression of cauda equina. The L4 level of spinal cords were harvested at 2 weeks,4 weeks,8 weeks,and 12 weeks after operation in the experimental group,and at 4 weeks in the control group respectively,and then immunohistochemistry and image analysis were performed to observe the expression of iNOS in spinal cord and the TUNEL method was applied to observe cell apoptosis. The morphology of cells was observed by transmission electron microscope. Results There was few amount of iNOS expressed in the control group. The expression of iNOS was slight at 4 weeks in the experimental group and was higher at 8 weeks and 12 weeks compared with the control group. Small amount of neural cell apoptosis was evidenced in the control group,while neuron apoptosis appeared remarkably in the experimental group since 4 weeks and increased with the extension of time. Transmission electron microscopy found apoptosis changes in neurons in the experimental group. Conclusion The expression of iNOS increases in corresponding spinal cords after chronic compression of cuada equine and neural cell apoptosis oc?curs,indicating that iNOS is positively correlated with neural cell apoptosis.