P2Y1受体介导星形胶质细胞的激活在急性一氧化碳中毒迟发性脑病中的作用

Effect of P2Y1 receptor activation on astrocytes in delayed encephalopathy after acute carbon monoxide poisoning

目的探讨P2Y1受体和星形胶质细胞在急性一氧化碳(CO)中毒迟发性脑病(DEACMP)中的作用以及DEACMP可能的发病机制。方法经水迷宫实验筛选认知功能合格的雄性SD大鼠,随机分为两组:对照组、CO中毒组,CO中毒组制作DEACMP模型,分别于造模后第7天、第14天、第21天、第28天对比两组行为学改变,神经元变化以及海马组织中P2Y1受体和星型胶质细胞的表达。结果通过水迷宫发现与对照组相比,造模后第21天、第28天CO中毒组大鼠逃避潜伏期均明显延长(P<0.05);HE染色发现造模后第14天、第21天、第28天模型组大鼠海马锥体细胞及神经元坏死明显,结合水迷宫可表明大鼠在21 d时出现DEACMP;与对照组相比,Western blot法检测提示各时间点CO中毒组海马区P2Y1及GFAP蛋白表达均增多(P<0.05),呈先升高后降低的趋势;免疫荧光表明海马区P2Y1和GFAP存在共表达,相对于对照组,中毒后各时间点海马CA 1区P2Y1和GFAP都有表达上调(P<0.05)。结论P2Y1受体对星形胶质细胞的激活可能是DEACMP的发病机制之一,星形胶质细胞可能通过介导免疫炎症反应使CO中毒的大鼠学习记忆能力损害导致DEACMP发生。

Objective To investigate the role of P2Y1 receptors and astrocytes in delayed encephalopathy after acute CO poisoning(DEACMP)and the possible pathogenesis of DEACMP.Methods Male SD rats with acceptable cognitive function were screened by water maze test and randomly divided into two groups:the control group and the CO poisoning group.The poisoning group was subjected to DEACMP model.The behavioral changes,neuronal changes and the expressions of P2Y1 receptor and astrocytes in hippocampus of the two groups were compared at 7,14,21 and 28 d after modeling,respectively.Results Compared with the control group,the escape latencies of rats in the poisoning group were significantly prolonged on the 21st and 28th days after modeling(P<0.05).HE staining showed that the hippocampal pyramidal cells and neurons in the model group exhibited obvious necrosis on days 14,21,and 28 after modeling.The water maze indicated that DEACMP occurred on day 21.Compared with the control group,Western blot analysis showed that the expression levels of P2Y1 and GFAP proteins in the hippocampus of the poisoning group were increased at each time point(P<0.05),which increased first and then decreased.Immunofluorescence showed co-expression of P2Y1 and GFAP in hippocampus.Compared with the control group,the expressions of P2Y1 and GFAP in hippocampal CA 1 region were up-regulated at each time point after poisoning(P<0.05).Conclusion The activation of astrocytes by P2Y1 receptor may be one of the pathogenesis of DEACMP,and astrocytes may impair learning and memory ability of co-poisoned rats by mediating immune inflammation,leading to DEACMP.