Correa-Rotter R, Pérez-Castillo A, Chmielewski D, Rosenberg M E
Department of Medicine, University of Minnesota, Minneapolis 55455.
Nephron. 1992;62(3):322-7. doi: 10.1159/000187067.
Postnatal nephrogenesis and growth of the rat kidney is greatest during the first 10 days of life. The renin-angiotensin system has important growth-promoting effects. To explore the relationship between postnatal renal development and the renin-angiotensin system, we examined the steady-state levels of messenger ribonucleic acid (mRNA) for renin, angiotensinogen, histone H2b (a marker of DNA synthesis) and the structural protein actin. The pattern of expression for renin and histone H2b were similar, with maximal levels of both mRNAs occurring during the first 10 days of life, the time of most marked postnatal nephrogenesis and kidney growth. A different pattern was seen for angiotensinogen mRNA, with low to undetectable levels during the first 15 days of life, and for actin mRNA, with fairly stable expression at the time points examined, providing evidence that the increase in renin and histone H2b mRNA was not due to a nonspecific increase in mRNA in the newborn kidney. In conclusion, the increase in renal histone H2b mRNA during the early postnatal period is consistent with this being a time of increased DNA synthesis. The similar time course for renin mRNA, histone H2b mRNA and previously defined changes in postnatal nephrogenesis suggests a role for the renin-angiotensin system in postnatal nephron formation.
大鼠肾脏的产后肾发生和生长在出生后的前10天最为显著。肾素-血管紧张素系统具有重要的促生长作用。为了探讨产后肾脏发育与肾素-血管紧张素系统之间的关系，我们检测了肾素、血管紧张素原、组蛋白H2b（DNA合成的标志物）和结构蛋白肌动蛋白的信使核糖核酸（mRNA）的稳态水平。肾素和组蛋白H2b的表达模式相似，两种mRNA的最高水平都出现在出生后的前10天，即产后肾发生和肾脏生长最显著的时期。血管紧张素原mRNA呈现出不同的模式，在出生后的前15天水平较低至无法检测到，而肌动蛋白mRNA在检测的时间点表达相当稳定，这表明肾素和组蛋白H2b mRNA的增加并非由于新生肾脏中mRNA的非特异性增加。总之，产后早期肾脏组蛋白H2b mRNA的增加与这是一个DNA合成增加的时期相一致。肾素mRNA、组蛋白H2b mRNA的相似时间进程以及先前确定的产后肾发生变化表明肾素-血管紧张素系统在产后肾单位形成中起作用。
