Objective To investigate the effects of warming-needle acupuncture on the levels of matrix metalloproteinase-1 (MMP-1) and interleukin-1β (IL-1β) in the articular cartilage in knee osteoarthritis induced by immobilization in rabbits.MethodsA total of 30 adult male Japanese white rabbits were randomly assigned into three groups by random number table method: a normal group, a model group and a treatment group, with 10 rabbits in each group. Knee osteoarthritis was induced by 6 weeks of immobilization. The rabbits in the treatment group received warming-needle acupuncture after modeling at points of “Neixiyan” (EX-LE4), “Dubi” (ST35), “Zusanli” (ST36) and “Yanglingquan” (GB34) for 4 weeks. The level of MMP-1 and IL-1β in the articular cartilage of the knee were determined with radioimmunological assay.ResultsThere were significant difference in the levels of MMP-1(0.16 ± 0.02 ng/mg, 0.37 ± 0.02 ng/mg, and 0.28 ± 0.03 ng/mg;F=258.251) and IL-1β (0.21 ± 0.01 pg/mg, 0.34 ± 0.02pg/mg, and 0.31 ± 0.04 pg/mg;F=127.112) among the normal group, model group and treatment group. The levels of MMP-1 and IL-1β both in the model group and treatment group were significant higher than those in the normal group (allP<0.01), while the levels of MMP-1 and IL-1β in the treatment group were significant lower than those in the model group (allP<0.01).ConclusionWarming-needle acupuncture can effectively reduced the levels of MMP-1 and IL-1β in the articular cartilage in knee osteoarthritis induced by immobilization in rabbits.