Expression And Clinical Significance Of COX-2 And PGE2 In Lumbar Disc Herniation

Objective : To investigate the expression of cyclooxygenase-2(COX-2) and prostaglandin E2(PGE2) in lumbar disc herniation and explore their significance in the pathogenesis of intervertebral disc degeneration and lumbar disc hernaiton. Furthermore, to study the association between the expression of COX-2,PGE2 and sciatica.Methods: 42 discs from patients with lumbar disc herination(12 protrusion type,15 extrusion type,15sequestration type) were collected. The specimens were obtained from two zone of disc: A zone was hernia tissue or separate fragment , B zone was the remainder nucleus pulpous of lumbar intervertebral disc. Patients'sciatica pain were evaluated by a visual analog scale and oswestry preoperatively. In control group, 5 normal discs were harvested from 1 young fresh autopsy. The specimens were obtained from two zone of disc: A zone was the margin of lumbar intervertebral disc , B zone was the center nucleus pulpous of lumbar intervertebral disc. The expression of COX-2 and PGE2 were evaluated enzyme-linked immunosorbent assay, and their content by the sample OD values found in the standard curve were assay. Their final content were expressed by ng/gm,pg/gm respectly.Results: COX-2 and PGE2 were overexpressed in LDH group compare with those in control group(P<0.01). Three different types of herniation have different expressions of COX-2 and PGE2 statistically(P<0.01). The expression of COX-2 and PGE2 were higher in extrusion and sequestration type as compared with protrusion type(P<0.01). The expression of COX-2 and PGE2 were different in two zone of LDH group(P<0.01). A positive correlation was found between the expression of COX-2 and PGE2 in LDH group (r=0.863, P<0.01). Three different types of LDH have different VAS and Oswestry score of sciatica statistically(P<0.01). The VAS pain score of sciatica were positive correlated with the expression of PGE2 in LDH group(r=0.848, P<0.01). The Oswestry score of sciatica were positive correlated with the expression of PGE2 in LDH group(r=0.833, P<0.01).Conclusion: COX-2 and PGE2 were involved in the pathogenesis of lumbar disc degeneration and lumbar disc hernaiton. COX-2 and PGE2 play critical role in the development of lumbar disc degeneration and herniation. COX-2 might play a key role in the expression of PGE2 in LDH. The content of PGE2 are closely related with the degree of sciatica.