OBJECTIVETo observe the therapeutic effect of acupoint application with Leima type II plaster on collagen-induced arthritis (CIA) in rats and probe its mechanism.

METHODSBovine type II collagen was injected intradermally into the middle line of the back to induce CIA model with 48 Wistar rats. Then the rats were randomly divided into a model control group (group A), a matrix control group (group B), acupoint application group with plaster of low concentration (group C) and high concentration plaster group (group D), 12 rats in each group. Group C and group D were treated with low and high concentration of Leima type II plaster, and "Shenzhu" (GV 12), "Zhiyang" (GV 9) and "Mingmen" (GV 4) were selected, each application for about 15 hours, once each day for 30 days. Group B was used the same method of acupoint application except using non-drug matrix plaster, and group A was not given any treatment. The morphous and the histopathological changes of affection joint were observed.

RESULTSThe paw edema volume after 30 days treatment in group C was significantly lower than that in group B (P < 0.01), and the anti-type II collagen antibody level after 15 days treatment in group C was significantly lower than that in group A (P < 0.05), and the synoviocytes proliferation of the knee joint in group C was significantly lower than that in group A and group B (both P < 0.01). The paw edema volume after 25 days treatment, arthritic index after 20 days treatment, pathological change of the paw and the synoviocytes proliferation of the knee joint in group D were significantly lower than those in group A and group B (P < 0.01, P < 0.05), and the anti-type II collagen antibody level after 15 days treatment in group D was significantly lower than that in group A (P < 0.05), and the paw edema volume and the arthritic index after 25 days treatment in group D were significantly lower than those in group C (P < 0.05, P < 0.01).

CONCLUSIONAcupoint application with Leima type II plaster has a good therapeutic effect on CIA rats and the protective mechanism is related to the reduction of anti-type II collagen antibody level so as to carry out anti-inflammatory effect and immunosuppression.