水通道蛋白1、2、5在膜迷路积水豚鼠耳蜗中的分布及表达研究

目的观察水通道蛋白(aquaporin,AQ)1、2、5(AQP1、AQP2、AQP5)三种蛋白在膜迷路积水豚鼠耳蜗的表达及分布情况,探讨其在内淋巴积液中可能的发生机制。方法选择健康红目豚鼠60只,随机分为空白组(30只)和模型组(30只),模型组给予醋酸去氨加压素6μg·kg-1·d-1腹腔注射10 d,空白组以1 ml生理盐水腹腔注射10 d;常规饲养7天后取出耳蜗,通过免疫组化、Western-blot方法观察AQP1、AQP2、AQP5蛋白在豚鼠耳蜗的分布及表达。结果免疫组化示空白组、模型组豚鼠耳蜗组织中AQP1表达的光密度值分别为0.134±0.021、0.273±0.053;AQP2表达分别为0.089±0.013、0.261±0.100;AQP5表达分别为0.264±0.065、0.151±0.098;与空白组比较,模型组AQP1、AQP2蛋白表达明显上调(P<0.01),AQP5蛋白表达明显下调(P<0.05)。Western-blot示空白组、模型组豚鼠耳蜗组织中AQP1表达分别为0.214±0.034、0.313±0.032;AQP2表达分别为0.283±0.050、0.544±0.042;AQP5表达分别为0.291±0.041、0.199±0.033;与空白组比较,模型组AQP1、AQP2蛋白表达上调(P<0.01),AQP5蛋白表达明显下调(P<0.05)。结论AQP1、AQP2、AQP5蛋白均可能参与了豚鼠耳蜗膜迷路积水的发生。

Distribution and Expression of AQP1,AQP2 and AQP5 Proteins in the Cochlea of Guinea Pigs with Membranous Labyrinthine Hydrops

Objective To study the expression and distribution of AQP1,AQP2 and AQP5 proteins in the cochlea of guinea pigs with membranous labyrinth hydrops,and the possible mechanism of AQP1,AQP2 and AQP5 proteins in endolymphatic effusion.Methods Sixty-four healthy red-eye guinea pigs,half male and half female,were randomly divided into blank group(30)and model group(30).The model group was given 6μg/kg/d intraperitoneal injection for 10 days.The blank group was intraperitoneally injected with 1 ml saline for 10 days.Samples were taken after 7 days of routine feeding.Among them,30 were taken from blank group and 30 from model group.The distribution and expression of AQP1,AQP2 and AQP5 proteins in the cochlea of guinea pigs were observed by immunohistochemistry and Western-blot.Results The optical density value of AQP1 expression in cochlear tissue of guinea pigs in blank group and model group was 0.134±0.021 and 0.273±0.053,respectively by immunohistochemical method.The expression of AQP2 was 0.089±0.013 and 0.261±0.100,and the expression of AQP5 was 0.264±0.065 and 0.151±0.098,respectively.The results of immunohistochemistry showed that compared with the blank group,the expression of AQP1 and AQP2 protein in the model group was significantly increased(P<0.01),while the expression of AQP5 protein in the model group was significantly decreased(P<0.01).Western-blot method showed the expression of AQP1 in the cochlear tissues of guinea pigs in blank group and model group:0.214±0.034,0.313±0.032,respectively.The expression of AQP2 was 0.283±0.050 and 0.544±0.042,respectively.The expression of AQP5 was 0.291±0.041 and 0.199±0.033 respectively.Western-blot results showed that compared with the blank group,the expression of AQP1 and AQP2 protein in the model group was also up-regulated(P<0.01),while the expression of AQP5 protein in the model group was down-regulated(P<0.01).Conclusion AQP1,AQP2 and AQP5 proteins were involved in the occurrence of cochlear labyrinth hydrops in guinea pigs.