二甲基苯蒽对金属硫蛋白基因敲除小鼠免疫功能的影响  

Effect of 7,12-dimethylbenz(a)athrancene on immune function in metallothionein gene-knocked-out mice

作　　者：雷志明[1] 阮明[1] 邱飞婵[1] 魏雪涛[1] 李雪婷[1] 贾凤兰[1] 尚兰琴[1] 张宝旭[1] 

机构地区：[1]北京大学公共卫生学院毒理系,100083

出　　处：《中华预防医学杂志》2002年第6期398-401,共4页Chinese Journal of Preventive Medicine

基　　金：国家自然科学基金资助课题 (3 9970 64 8)

摘　　要：目的　观察二甲基苯蒽 (DMBA)对金属硫蛋白 (MT)基因敲除小鼠 [MT(- / - ) ]的免疫毒性。方法　选用MT(- / - )小鼠和MT(+/ +)野生型小鼠进行对照 ,DMBA 2 5mg/kg和 5 0mg/kg分别 1次腹腔注射染毒后 ,检测动物对静脉注射绵羊红细胞 (SRBC)诱导的体液和细胞免疫反应。体液免疫指标为脾脏抗体形成细胞 (PFC)数量变化。细胞免疫功能指标选择迟发型变态反应 ,即动物足跖肿胀厚度变化。结果　DMBA 2 5mg/kg组 ,MT(- / - )小鼠脾脏和胸腺重量都减轻、体液免疫功能受到抑制 (抑制率为 72 % ) ,而MT(+/ +)小鼠仅脾脏重量减轻。两种小鼠的细胞免疫功能均未见明显变化。DMBA 5 0mg/kg组 ,MT(- / - )小鼠的体液免疫和细胞免疫功能受到抑制程度均比DMBA2 5mg/kg组严重 (抑制率分别为 91%和 72 % )。MT(+/ +)小鼠虽脾脏和胸腺重量减轻、体液免疫受到抑制 ,但变化程度明显小于MT小鼠 (- / - )。MT(+/ +)小鼠没有出现明显的细胞免疫功能抑制。结论　MT(- / - )小鼠的体液免疫和细胞免疫功能更易被DMBA抑制。Objective To study the immunotoxicity induced by 9,10 dimethyl 1,2 benzathrancene (DMBA) in metallothionein gene knocked out mice as compared with that in wild type mice Methods Female mice were treated with 25 mg/kg and 50 mg/kg of DMBA i p , respectively and immunized with sheep red blood cells (SRBC) i v on the following day and rechallenged by injection of SRBC via footpad s c on the fourth day post immunization Humoral and cell mediated immune function was assessed by the number of spleen IgM antibody plaque formation cells (PFC) to SRBC and cell mediated delayed type hypersensitivity (DTH) measured by footpad swelling thickness Results After treatment with 25 mg/kg DMBA, a decrease in weight of their spleen and thymus and PFC/spleen were observed in MT (-/-) mice, while only decrease in thymus weight of MT(+/+) mice The humoral function was suppressed by 72% in MT (-/-) mice No obvious change in cell mediated immune function was observed both in MT (-/-) and MT(+/+) mice Both humoral and cell mediated immune function were suppressed more severe (91%) in MT (-/-) mice treated with 50 mg/kg DMBA than those treated with 25 mg/kg DMBA (72%) DTH was not altered by DMBA in MT (+/+) mice The weight of their spleen and thymus decreased and humoral immune function suppressed in MT(+/+)mice, but these changes were significantly less severe No obvious suppression of cell mediated immune function was observed in MT(+/+)mice Conclusion Their humoral and cell mediated immune function was more susceptible to being suppressed by DMBA in MT (-/-) mice, indicating that MT could protect their immune function from damage caused by DMBA

关 键 词：二甲基苯蒽 金属硫蛋白 小鼠 免疫功能 

分 类 号：R114[医药卫生—卫生毒理学]