急性酒精中毒合并中度创伤性脑损伤大鼠海马AQP4的表达

目的:探讨大鼠急性酒精中毒合并颅脑外伤后AQP4在海马区表达的变化.方法:健康成年雄性SD大鼠96只,随机分为4组:假手术组(N组)、急性酒精中毒组(A组)、中度创伤性脑损伤组(T组)和急性酒精中毒合并中度创伤性脑损伤(AT组).腹腔注射酒精(2.5g/kg),2h后以重物自由落体击打大鼠头部建立急性酒精中毒合并中度创伤性脑损伤(traumatic brain injury,TBI)动物模型.各组动物分别存活1、3、5、14天.免疫组化方法检测海马CA1区AQP4的表达.结果:AQP4阳性产物分布于胶质纤维和毛细血管壁,各实验组表达均高于N组.术后1天T组比AT组表达显著增高(P＜0.01),术后3天AT组比T组表达增高(P＜0.05),术后14天AT组比T组表达显著增高(P＜0.01).结论:大鼠急性酒精中毒合并颅脑外伤后晚期,海马CA1区AQP4表达增高,可能加重晚期继发性脑水肿,是急性酒精中毒合并颅脑外伤预后不良的原因之一.

Research of Expressions of AQP-4 in Hippocampus of Rats after Acute Alcoholism with Traumatic Brain Injury

Objective:To investigate the expression changes and roles of AQP4 in rat hippocampus under condition of acute alcohol intoxication with TBI.Methods:The animal model of acute alcohol intoxication with TBI was established by injecting of 20% alcohol intraperitoneally and hitting rat forehead vertically.96 SD male rats were randomly divided into four groups:N group (normal saline was injected into the rat abdominal cavity),A group (alcohol was injected into the rat abdominal cavity),T group (before Waumatic brain injury,normal saline was injected into the rat abdominal cavity) and AT group (before traumatic brain injury,alcohol was injected into abdominal cavity and traumatic brain injury).Animals of every group survived 1,3,5,14 days respectively.The expression of AQP4 in hippocampus neurons was detected by immunohistochemistry.Results:Positive product of AQP4 distribute in the glial fibers and capillaries wall.The expression of AQP4 in Experimental group were higher than the N group,Group T were more higher than that in Group A at 1 day(P＜0.01),Group AT were higher than that in Group T at 3 day(P＜0.05),Group AT were more higher than that in Group T at 14 day (P＜0.01).Conclusion:Acute alcoholism plays protective roles at early stage of moderate traumatic brain injury,which may be related to astrocyte inhibited by alcohol so as to reduce inflammatory reaction.