幼龄SHR大鼠肾脏内皮素系统的改变

目的 观察幼龄高血压大鼠肾脏内皮素－1（ET－1）及其A、B受体的改变。方法 采用免疫组化和RT－PCR方法检测7周龄SHR大鼠肾脏ET－1及其A、B受体mRNA和蛋白水平。结果 与WKY对照组相比，SHR大鼠存在明显的高血压和尿钠、尿量排泄下降，血浆及肾组织中ET含量无显著异常，但是肾血管ETA受体的mRNA和蛋白水平明显升高，而肾脏ET－1及B受体的表达无改变。结论 肾血管ETA受体明显上调可能参与了幼龄高血压大鼠肾脏水钠潴留。

Changes of Endothelin System in the Kidney of Young Spontaneously HypertensiveRats

Purpose To investigate the changes of endothelin 1(ET?1) and its receptors in the kidney of young spontaneously hypertensive rat(SHR). Methods Immunohistochemistry and RT PCR method were used to measure the amount of protein and mRNA expressions of ET 1 and their receptors in the kidney of 7 week old SHR.Mean arterial blood pressure,urinary volume,urinary sodium excretion as well as plasma and renal endothelin levels were also measured at the same time. Results The enhanced blood pressure as well as decreased urinary volume and sodium excretion were observed in young SHR compared to age matched wistar kyoto(WKY)rats.Neither plasma nor renal endothelin level was changed significantly.However,the expression of endothelin A type receptor mRNA and protein in the smooth muscle cells of intrarenal arteries were increased markedly in young SHR compared to WKY.ET?1 and its B type receptor expression were not altered in the kidney of young SHR and WKY rats. Conclusions The upregulation of vascular endothelin receptor A in the kidney may mediate the abnormal renal hemodynamics in young SHR.