To investigate the effects of electroacupuncture at two points of piriform muscle on the expression of interleukin-6(IL-6)，nitric oxide(NO)，prostaglandin 2(PGE2)，and matrix metalloproteinase 3(MMP-3) in the serum of model rats of lumbar disc herniation.Methods:A total of 32 SD rats were randomly assigned into a blank group，a model group，and electroacupuncture groups 1 and 2，with 8 rats in each group.Except the blank group，the other 3 groups were modeled according to the modeling method of non-compressive model of nucleus pulposus of lumbar intervertebral disc.Electroacupuncture groups 1 and 2 were treated with the corresponding intervention measures.At the end of modeling and on the 1st，3rd，and 6th days of treatment，the hind paw withdrawal threshold was measured.The serum levels of IL-6，NO，PGE2，and MMP-3 were measured by enzyme-linked immunosorbent assay(ELISA) after 6 days of treatment.Results:Three days after modeling，the paw withdrawal thresholds in the model group and electroacupuncture groups 1 and 2 declined compared with that in the blank group(P<0.01).The paw withdrawal threshold in the model group showed no significant difference before and after 6 days of treatment(P>0.05).The electroacupuncture increased the paw withdrawal threshold compared with that before treatment(P<0.01).The levels of IL-6，NO，PGE2，and MMP-3 in electroacupuncture groups 1 and 2 were lower than those in the model group(P<0.01).Conclusion:Electroacupuncture at two points of piriform muscle can down-regulate the expression of IL-6，NO，PGE2，and MMP-3 in the serum to exert the anti-inflammatory and pain-relieving effects on lumbar disc herniation in model rats.