沙鼠脑缺血再灌注后PHF-1和58K-9表达的变化及美满霉素干预的影响

目的研究沙鼠脑缺血再灌注后脑内磷酸化的Tau蛋白（PHF-1）和高尔基体表面蛋白标记抗体（58K-9）表达的变化及美满霉素干预对它们表达的影响。方法采用夹闭双侧颈总动脉的方法制作沙鼠脑缺血再灌注模型；50只沙鼠随机分为正常对照组、假手术组、缺血再灌注组、美满霉素干预组（美满霉素干预＋缺血再灌注）；美满霉素干预组的沙鼠在实验前1d开始腹腔注射美满霉素（剂量为45mg／kg，Bid）；缺血再灌注组、美满霉素干预组分别在缺血再灌注（IR）后6h、1d、3d、7d的各时间点分批处死动物，快速取脑组织制作标本，采用免疫组织化学方法检测各组沙鼠脑内PHF-1、58K-9的表达水平。结果（1）正常对照组与假手术组沙鼠脑组织中可见少量PHF-1的阳性表达，2组比较无差别（P〉0．05），且阳性信号主要位于神经元和胶质细胞胞浆中；缺血10min分别再灌注3d、7d后脑组织中PHF-1表达增加，7d组表达高于3d组；3、7d组与正常对照组及假手术组比较差异有显著性（P〈0.01）；（2）正常对照组与假手术组沙鼠脑组织中可见大量58K-9的阳性表达，2组比较无差别（P〉0．05），且阳性信号主要位于神经元和胶质细胞胞浆中；缺血10min分别再灌注3、7d后脑组织中58K-9表达减少，7d组表达低于3d组；3、7d组与正常对照组及假手术组比较差异有显著性（P〈0．01）；（3）美满霉素干预组在缺血t0min再灌注6h、1、3、7d时沙鼠脑组织中PHF-1、58K-9表达趋势同缺血再灌注组，但3、7d组PHF-1阳性率明显低于缺血再灌注组，58K-9阳性率高于缺血再灌注组，相同时间点比较差异有显著性（P〈0.01）。结论（1）沙鼠脑缺血再灌注后脑组织PHF-1表达增高，提示Tau蛋白发生高度磷酸化改变；58K-9表达减少，提示高尔基体结构与功能的损坏；（2）美满霉素干预可使沙鼠脑缺血再灌注后脑组

Expressions of PHF-1 and 58K-9 in ischemia-reperfusion brain tissue of gerbils and the intervention effect of minocycline

Objective To investigate the expressions of PHF-1 and 58K-9 in ischemia-reperfusion brain tissue of gerbils and the intervention effect of minocyeline. Methods A cerebral ischemia reperfusion model in gerbils was established by clamping both common carotids. Fifty gerbils were randomly divided into four groups ： normal control group, sham operation group, ischemia-reperfusion（IR） group and minocycline intervention group, in which minocycline（45 mg/kg,Bid） were injected into gerbils＇ abdominal cavity twice a day in the intervention group from the day before experiment. The gerbils were sacrificed in batch and the brain tissue was guickly obtained to make the samples at the 6th hours, 1st day, 3rd and 7th day after IR. The expression of PHF-1 and 58K-9 in brain tissue was detected by using immunohistochemistry technique at the 6th hours, 1st day,3rd and 7th day after IR. Results Our experimental results revealed that PHF-1 and 58K-9 were expressed in neurons and gliacytes of the brain tissue in 50 gerbils. There was few expression of PHF-1 while numerous experession of 58K-9 in neurons and gliacytes in both normal control group of 5 gerbils and sham oper- ation group of 5 gerbils, and there was no significant difference between the two groups （ P〉0. 05）. Compared with normal control group, the expressions of PHF-1 in neurons and gliacytes of ischemia-reperfusion gerbils increased evidently while 58K-9 decreased on the 3rd day and 7th day, especially on the 7th day（P〈0. 01）. The expression of PHF-1 and 58K-9 on the 3rd day and 7th day in minocycline intervention group was obviously different from that in the IR group （P〈0. 01）. Conclusions （1）The expression of PHF-1 in neurons and gliacytes of gerbils evidently increases following cerebral ischemia-reperfusion which suggests the hyphosphorylation of Tau protein following cerebral ischemia-reperfusion and the expression of 58K-9 decreases which suggests the damage of the Golgi apparatus. （2）The damage of brain tissue following c