AQP-9在大鼠感染性脑水肿脑组织中的表达及意义

目的 探讨水通道蛋白-9(AQP-9)在内毒素脂多糖(LPS)致大鼠感染性脑水肿脑组织中的表达及意义. 方法 1月龄普通级SD大鼠128只采用随机数字表法分为生理盐水(NS)组(64只)和LPS组(64只),采用颈内动脉注射LPS制作大鼠感染性脑水肿模型,模型成功后每组均选取6h、12h、24h和48 h4个时间点,在不同时间点采用HE染色观察脑组织形态学改变;干湿重法测定脑组织含水量(BWC);甲酰胺法测定脑组织伊文思蓝(EB)含量;免疫组织化学法检测脑组织AQP-9蛋白的表达量:采用逆转录多聚酶链反应(RT-PCR)方法 检测AQP-9 mRNA的表达水平并对结果 进行相关性分析. 结果 HE染色结果 显示LPS组血管周围间隙增宽、炎性细胞浸润、胶质细胞体积增大肿胀、神经元空泡变性、细胞核固缩等.与NS组相比,LPS组6 h、12 h、24 h和48 hBWC、EB含量、AQP.9蛋白及AQP.9mRNA表达水平均增高.差异具有统计学意义(P<0.05).同时LPS组BWC和EB含量、AQP-9蛋白、AQP.9 mRNA表达量、AQP-9 mRNA表达量与EB含量、AQP-9蛋白与mRNA表达量均呈正相关. 结论 AQP-9可能参与感染性脑水肿的发生和发展.

Expression of aquaporin-9 in the brain tissue of rats with infectious brain edema

Objective To investigate the expression of aquaporin-9(AQP-9)in the brain tissue of rats with infectious brain edema and explore the role of AQP-9 in the oecurrgnce and progression of the brain edema. Methods A total of 128 normal 1-month-old SD rats weighing 70-100 g of either sex were randomly divided into two equal groups, namely the normal saline(NS) group and lipopolysaecharide(LPS)group.Acute infectious brain edema was induced in rats in the LPS group by injecting LPS via the left internal carotid artery,and the rats in the NS groups received NS injection.At 6,12,24 and 48 h after the injection,the brain tissue was taken from the rats to observe the histopathology by Hernatoxylin-Eosin Stain and lneasure the brain water content(BWC).The permeability of the blood-brain barrier of the rats was tested using Evans blue(EB)method.The expressions of AQP-9 protein and mRNA in the brain tissue Were detected using immunohistochemistry and RT-PCR,respectively. Results InLPS group,the space around the blood vessels was obviously broadened in the brain tissue,where inflammatory cell infiltration,glioeyte swelling,vacuolar degeneration of the neurons and neuronal nuclear shrinkage were seen.At 6,12,24,and 48 h following LPS or NS injection,the BWC,EB content,and expressions of AQP-9 protein and mRNA in the LPS group were all significantly higher than those in the NS group(P<0.05),In the LPS group,positive correlations were found between BWC and EB content,AQP-9 protein expression and BWC,AQP一9 mRNA and BWC,AQP-9mR.NA and EBcontent,and between AQP-9 protein andmRNA.Conclusion AQP-9 might participate in occurrcnce and development of infectious brain edema in rats,it might be positive correlation.