Abstract: Objective To observe the effects of deep electroacupuncture on carlilage tissue in knee osteoarthritis (KOA) rabbits. Methods 40 New Zealand rabbits were randomly divided into normal group (A, n=10) and model group (n=30). The model group was modeled KOA with Hulth-Telhag way, and identified with X-ray. Then they were divided into no-treated group (B, n=10), deep electroacupuncture group (C, n=10) and routine electroacupuncture group (D, n=10) randomly. The groups C and D accepted electroacupuncture since 6 weeks after modeling, for 4 weeks. They were measured with pH of joint fluid, observed structure and pathology of cartilage under transmission electron microscope, detected apoptosis index, and determined the expression of acid-sensing ion channel 1 (ASIC1), p38 mitogen-activated protein kinases (p38MAPK) and p53 with Western blotting, and distribution of ASIC1 with immunohistochemistry in cartilage tissue. Results The pHs of joint fluid from high to low were ranged as the groups A=C>D>B (P<0.01). The cartilage structure was more complete in the groups A, C and D than in the group B. The apoptosis rates from less to more were ranged as the groups A=C

Key words: knee osteoarthritis, electroacupuncture, deep acupuncture, apoptosis, acid-sensing ion channel 1, p38 mitogen-activated protein kinases, p53, rabbits