醛固酮对肾小球系膜细胞合成分泌纤维连接蛋白的影响

Aldosterone regulates synthesis of fibronectin in cultured rat mesangial cells

目的研究醛固酮(aldosteroen,ALD)及其受体拮抗剂螺内酯(spironolactone,SPI)对大鼠肾小球系膜细胞合成分泌纤维连接蛋白(fibronectin,FN)的影响。方法以不同浓度的ALD(10-11、10-9、10-7mol/L)和/或10-7mol/L SPI刺激系膜细胞48 h后,应用酶联免疫吸附试验(ELISA)测定培养上清中FN的浓度,应用半定量反转录-聚合酶链反应(RT-PCR)检测细胞FN mRNA的表达;以10-9mol/L浓度的ALD刺激系膜细胞不同时间(24、48、72 h)后,应用ELISA测定培养上清中FN的浓度,应用半定量RT-PCR方法检测细胞FN mRNA的表达。结果ELISA结果显示,ALD促进大鼠肾小球系膜细胞合成分泌FN,且具有浓度依赖和时间依赖性的特点,SPI能够拮抗ALD的作用。半定量RT-PCR方法结果显示,ALD促进培养的大鼠肾小球系膜细胞FN mR-NA的表达,且具有浓度依赖和时间依赖性的特点,SPI能够拮抗ALD的作用。结论ALD从蛋白和基因水平促进大鼠肾小球系膜细胞合成分泌FN,且具有浓度依赖和时间依赖性的特点,SPI能够拮抗ALD的作用,从而可能有益于延缓肾小球硬化的进展。

Objective To evaluate the effect of aldosterone and its antagonist on the synthesis and secretion of fibronectin （FN） in cultured rat mesangial cells. Methods ①Mesangial cells were treated with medium containing different concentrations of aldosterone （10^-11,10^-9,10^-7mol/L） and/or 10^-7 mol/L spironolactone for 48 h, while control cells were treated with vehicle only. The level of FN in the supernatants was measured by ELISA. The expressions of FN mRNA were detected by sinai-quantitative RT-PCR. ②Mesangial cells were treated with 10^-9 mol/L aldosterone for 24,48 and 72 h. The levels of FN in the supernatants were measured by ELISA. The expressions of FN mRNA were detected by semi-quantitative RT-PCR. Results ELISA method showed that the level of FN in the supematant of cultured rat mesangial cells stimulated with aldosterone increased significantly in a dose-and time-dependent manner. Also the expressions of FN mRNA were increased significantly by aldosterone in a dose-and time-dependent manner by semiquantitative RT-PCR. Spironolactone inhibited the stimulative effect of aldosterone on the synthesis of FN in cultured rat mesangial cells. Couclusion Aldosterone up-regulates the protein synthesis and mRNA expression of FN in cultured rat mesangial cells. Aldosterone antagonist inhibits the effect of aldosterone, and thus implication in the treatment of glomerulosclerosis.