水通道蛋白2在内淋巴囊上皮和肾脏中表达的研究

The Expression of Aquaporin-2,3,4 in Rats' Endolymphatic Sac and Kidney

陈婷;张榕;

1:福建省立医院耳鼻咽喉科

2:福建医科大学附属第一医院耳鼻咽喉科

摘要
目的探讨水通道蛋白2(Aquaporins 2,AQP-2)和加压素(anti-diuretic hormone,AVP)在内耳水代谢中的作有机制。方法15只(30耳)成年大鼠,随机分为三组,每组5只(10耳),A组(对照组):腹腔注射生理盐水;B组(AVP组):腹腔注射AVP(0.2 U/g);C组(DDAVP组):尾静脉注射V2受体促效剂去精氨酸加压素([deamino-Cys1,D-Arg8]-Vasopressin,DDAVP)1 ng/只。采用间接免疫荧光法标记内淋巴囊(endolymphaticsac,ES)中AQP-2的表达,ABC法标记肾脏中AQP-2的表达。结果AQP-2一抗在内淋巴囊上皮胞膜胞浆显示荧光染色,B组和C组的内淋巴囊上皮胞膜胞浆AQP-2的表达明显较A组降低(P<0.01);B组和C组AQP-2的表达则差异无显著统计学意义(P>0.05)。B组和C组肾脏集合管主细胞胞膜胞浆AQP-2的表达明显较A组增强(P<0.05),B组和C组AQP-2表达则差异无显著统计学意义(P>0.05)。结论AVP促进肾脏表达AQP-2,提高肾脏重吸收的功能,同时抑制内淋巴囊上皮表达AQP-2,从而降低内淋巴囊上皮对水的重吸收;AVP对肾脏和内淋巴囊AQP-2表达的调节可能是通过AVP-V2R-cAMP-AQP2途径实现。
关键词
水通道蛋白;内淋巴囊;肾脏;加压素;去精氨酸加压素;免疫组织化学;免疫荧光;大鼠
基金项目(Foundation):
福建省卫生厅创新基金资助(编号2003-cx-10)
作者
陈婷;张榕;
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