NAC对MTⅠ/Ⅱ敲除小鼠脑缺血再灌注后脾细胞损伤的保护作用

摘要

目的 观察金属硫蛋白(MT)Ⅰ/Ⅱ敲除小鼠脑缺血再灌注对脾细胞的影响,以及N-乙酰半胱氨酸(NAC)对其脾细胞损伤的保护作用.方法 6～8周龄健康雄性MT Ⅰ/Ⅱ敲除小鼠30只,随机分为假手术组、缺血再灌注组(I/R组)各15只.I/R组以左侧大脑中动脉线栓法制备小鼠局灶性脑缺血再灌注模型.假手术组不插线栓,余步骤同I/R组.再灌注24h后处死小鼠,分离脾细胞,脾细胞悬液给予NAC处理2h.MTT法检测两组NAC处理前后脾细胞活力、紫外分光光度计检测线粒体通透性转换孔(MPTP)开放情况、Ca2+转运情况,酶标仪测LDH活性.结果 NAC处理后,两组脾细胞活力均较处理前增大、MPTP开放程度降低、Ca2+转运减少、LDH活性增强(P均＜0.05).NAC处理后,I/R组较假手术组脾细胞活力降低、MPTP开放程度增大、Ca2+转运增加、LDH活性降低(P均＜0.05).结论 脑缺血再灌注后会导致MTⅠ/Ⅱ敲除小鼠脾细胞功能损伤,NAC可减轻其对脾细胞的损伤.%Objective To observe the effect of cerebral ischemia-repeffusion on splenocytes in MT Ⅰ / Ⅱ knockout mice and the protective effect of N-acetylcysteine (NAC).Methods A total of 30 MT Ⅰ / Ⅱ healthy male mice (aged 6 ～ 8 weeks) were randomly divided into 2 groups,15 in each group:the sham group and ischemia-reperfusion (I/R) group.The focal cerebral ischemia-reperfusion model in I/R group was established by middle cerebral artery thread-occlusionmethod.The mice in the sham group were established without thread-occlusion,and the remaining steps were the same.The mice in two groups were killed after 24 h reperfusion to obtain their spleen cells.Splenocytes suspension was treated with NAC for 2 h.The activity of splenocyte was measured by MTT method.The dilation of MPTP and Ca2+ channel working were measured by MPTP method.The activity of LDH was detected by LDH method.Results After treated with NAC,compared with pretreatment,the activity of splenocyte was enhanced,the dilation of MPTP and Ca2+ channel transport was reduced,and the activity of LDH was enhanced in both groups (all P ＜ 0.05).After treated with NAC,compared with the sham group,the activity of splenocyte was reduced,the dilation of MPTP and Ca2+ channel transport was enhanced,and the activity of LDH was reluced (all P ＜ 0.05).Conclusion Cerebral ischemia-reperfusion may lead splenocyte damage in MT Ⅰ / Ⅱ mice,but NAC has a protective effect for splenocytes in MT Ⅰ / Ⅱ mice after cerebral ischemia-reperfusion injury.