Rosnes J S, Valego N, Wang J, Zehnder T, Rose J C
Department of Obstetrics/Gynecology, Bowman Gray School of Medicine, Winston-Salem, North Carolina 27157, USA.
Am J Physiol. 1998 Jul;275(1):R141-7. doi: 10.1152/ajpregu.1998.275.1.R141.
We studied the pattern of plasma active renin concentration (ARC), prorenin concentration (PRC), renal renin concentration, and the renin mRNA levels in ovine fetuses subjected for 24 h to reduced renal perfusion pressure (RPP). The results obtained in five animals (133.8 +/- 1.4 days of gestation) in which RPP was reduced by 10 mmHg were compared with those in seven control fetuses (130.3 +/- 0. 8 days of gestation) without pressure reduction. Plasma samples were obtained before and at intervals of 24 h after initiating reduced RPP. The plasma ARC increased within 60 min of reduced RPP, reaching a maximum (13.0 +/- 4.7 vs. 115.7 +/- 23.8, P < 0.01) at 3 h. The ARC then declined toward control values. In contrast, plasma PRC did not increase consistently until 4 h into reduced RPP, with maximal levels at 24 h (8.2 +/- 2.4 vs. 87.7 +/- 21.9, P = 0.016). Within the kidney PRC, but not ARC, increased significantly, by 2.5-fold. Reduced RPP also increased renal renin mRNA levels (P = 0.004). We conclude that a chronic reduction in RPP in the near-term ovine fetus increases renal PRC and is associated with increased plasma prorenin levels. The data suggest that the conversion of prorenin to active renin is an important regulation point of the renin ANG system during development.
我们研究了肾灌注压（RPP）降低24小时的绵羊胎儿的血浆活性肾素浓度（ARC）、肾素原浓度（PRC）、肾内肾素浓度及肾素mRNA水平的变化模式。将5只妊娠133.8±1.4天、RPP降低10 mmHg的动物的结果与7只未降压的对照胎儿（妊娠130.3±0.8天）的结果进行比较。在降低RPP前及开始降低RPP后每隔24小时采集血浆样本。血浆ARC在RPP降低后60分钟内升高，3小时时达到最高值（13.0±4.7对115.7±23.8，P<0.01），随后ARC下降至对照值。相比之下，血浆PRC直到RPP降低4小时后才持续升高，24小时时达到最高水平（8.2±2.4对87.7±21.9，P = 0.016）。在肾脏内，PRC显著升高2.5倍，而ARC没有升高。降低RPP也使肾内肾素mRNA水平升高（P = 0.004）。我们得出结论，近足月绵羊胎儿的RPP慢性降低会增加肾脏PRC，并与血浆肾素原水平升高有关。数据表明，肾素原向活性肾素的转化是发育过程中肾素-血管紧张素系统的一个重要调节点。
