^99Tc-亚甲基二膦酸盐对胶原诱导性关节炎大鼠滑膜及软骨凋亡相关因子的影响

目的探讨^99Tc-亚甲基二膦酸盐（MDP）对胶原诱导性关节炎（CIA）大鼠的疗效，以及对滑膜和软骨细胞凋亡相关因子bcl-2、bax的影响。方法设立正常对照组；采用皮下注射法用牛Ⅱ型胶原和不完全弗氏佐剂诱导CIA大鼠模型，分为模型对照组（尾静脉注射生理盐水）、^99Tc-MDP组（每天1次尾静脉注射^99Tc-MDP，按体质量0．04μg ^99Tc／kg）和甲氨蝶呤（MTX）组（按体质量每周1次尾静脉注射MTX 1mg／kg），采用关节炎指数（AI）评价各CIA组大鼠关节炎程度，免疫组织化学染色法检测滑膜及软骨细胞bcl-2和bax表达；应用SPSS13．0软件对实验数据进行统计学处理。结果（1）^99Tc-MDP和MTX均能减轻CIA大鼠关节炎程度，降低AI评分，改善CIA大鼠关节滑膜炎的病理学变化。（2）与正常对照组[bcl-2：（7．56±1．18）％，bax：（6．14±1．71）％]比较，CIA模型对照组滑膜bcl-2和bax表达明显升高[（39．30±0．53）％、（27．37±2．45）％；q=46．27，24．57，P均〈0．001]；与模型对照组比较，^99Tc-MDP组和MTX组滑膜细胞bcl-2水平降低[（30．24±2．09）％、（27．25±3．33）％；q=13．20，17．56，P均〈0．001]，bax表达有所增加但差异无统计学意义，bcl-2／bax比值明显降低。（3）在软骨细胞中，CIA模型对照组bcl-2和bax表达[（20．20±2．78）％、（36．40±1．67）％]显著高于正常对照组[（9．91±4．09）％、（6．71±3．50）％；q=10．51，37．01，P均〈0．001]；与模型对照组比较，^99Tc-MDP组和MTX组bcl-2增高[（26．58±2．52）％、（27．06±1．92）％；q=6．53，7．01，P均〈0．001]，而bax水平降低[（24．26±2．75）％、（23．53±0．74）％；q=15．12，16．04，P均〈0．001]，bcl-2／bax比值增高。结论凋亡相关因子bcl-2和bax的异常表达与CIA的发生发展密切相关。^99Tc-MDP能够减轻CIA大鼠关节炎程度，调节滑膜和软骨细胞b

Effects of 99Tc-MDP on synoviocytes and articular chondrocytes apoptosis associated factors on CIA rats

Objective Collagen induced arthritis (CIA) rats is an animal model of human rheuma-toid arthritis (RA). It is widely used in research of the pathogenesis and the therapeutic targets of RA. This paper was to investigate the therapeutic action of 99Tc-methylene diphosphonic acid (MDP) on CIA rats and its effects on the expression of apoptosis associated factor bcl-2 and bax in synoviocytes and articular chon-drocytes. Methods CIA rat models were carried out by subcutaneous injection with bovine collagen Ⅱ and incomplete Freud's adjuvant. Rats were divided into four groups: control group, CIA model group (the CIA rats were infused with physiological saline via tail vein daily), 99Tc-MDP group (the C1A rats were injected with 99Tc-Mi)P 0.04 μg 99Tc/kg via tail vein daily) and methotrexate (MTX) group (the CIA rats were in-jected with MTX 1 mg/kg via tail vein weekly). The signs of arthritis were evaluated by arthritis index (AI) scores. Immunohistochemistry was performed to detect the expression of bcl-2 and bax in synoviocytes and articular chondrocytes. SPSS 13.0 was used for data analysis. Results (1) The signs of arthritis, AI scores and pathological changes of arthrosynovitis in CIA rats were significantly improved by 99Tc-MDP orMTX. (2) The expression of bcl-2 and box in the synoviocytes of CIA model group [(39.30 ± 0.53) %, (27.37 ±2.45)%] was significantly increased compared with control group [(7.56 ± 1. 18)% , (6.14 ± 1.71) % ; q = 46.27, 24.57, all P < 0.001]. In the synovioeytes of 99Tc-M DP group and MTX group, the level of bcl-2 was remarkably decreased [(30.24 ± 2.09) %, (27.25 ± 3.33) %] compared with CIA model group (q = 13.20, 17.56, all P <0.001), while the level of bax was slightly increased and the ratio of bcl-2/bax was significantly decreased. (3)The expression level of bcl-2 and bax in the articular chondro-cytes of CIA model group [(20.20 ± 2.78) %, (36.40 ± 1.67) %] was significantly higher than control group [(9.91±4.09)%, (6.71 ±3.50)%; q=10.51, 37.01, allP<0.001]. Compared with CIA model group, the expression level of bcl-2 in articular chondrocytes of 99Tc-MDP group [(26. 58 ± 2. 52) %] and MTX group [(27.06 ± 1.92) %] was remarksbly increased [(24.26 ± 2.75) %, (23.53 ± 0.74) % ; q = 6.53, 7.01, all P < 0.001]. And the expression level of bax was significantly decread (q = 15.12, 16.04, all P <0. 001) and the ratio of bcl-2/bax was significantly increased. Conclusions The ab-normal expression of apoptosis associated factor bcl-2 and bax in synoviocytes and articular chondrocytes was closely related to the occurrence and progression of signs in CIA rats. 99Tc-MDP could improve the signs of arthritis, meanwhile regulate the expression of bcl-2 and bax in synoviocytes and articular ehondrocytes, suggesting that one of the therapeutic mechanisms of 99Tc-MDP might be related to stimulated synoviocytes apoptosis and reduced articular chondrocytes apoptosis.