Abstract: Objective To investigate the expression and clinical signficance of monocyte chemoattractant protein-1(MCP-1) in nucleus pulposus of herniated lumbar discs. Methods The mRNA and protein expression of MCP-1 in the experimental group(48 fresh nucleus pulposus of patients with lumbar disc herniation)and control group(10 fresh nucleus pulposus of patients with traumatic lumbar vertebrae)were detected by semi-quantitative RT-PCR and immunohistochemical staining . Results (1)MCP-1 were overexpressed in LDH group compare with those in control group (P<0.01).In different types of herniation,the expression of MCP-1 were higher in external anulus rupture type as compared with that in external anulus intact type (P<0.01).Conclusion MCP-1 maybe an important regulatory factor in inflammatory changes of the herniated lumbar disc,it may play an initial role in the inflammatory reaction around the herniated discs.