Expression of matrix metalloproteinase 13 in degenerative and traumatic nucleus pulposus of intervertebral disc

Objective To compare the expression of matrix metalloproteinase 13(MMP-13) in the nucleus pulposus of degenerative and injured intervertebral disc,and to investigate the possible role of MMP-13 in the pathogenesis of intervertebral disc degeneration.Methods From January to July 2011,the nucleus pulposus was removed in 33 patients with protrusion of irtervertebral disc(degeneration group) and internal fixation was implanted in 6 patients with lumbar vertebral fracture(control group).Immunohistochemistry assay was used to detect the expression of MMP-13 in nucleus pulposus.The gray scale was measured with Image-ProPlus5.1 image analysis system.Results The expression of MMP-13 in degeneration group was significantly higher than that in control group([73.2±10.9]% vs.[20.4±14.3]%,P0.01).MMP-13 was darkly stained in degeneration group.Conclusion The expression of MMP-13 is significantly increased in the nucleus pulposus of degenerative intervertebral disc.And MMP-13 may play an important role in the development of the lumbar intervertebral degeneration.