Drukker A, Goldsmith D I, Spitzer A, Edelmann C M, Blaufox M D
Pediatr Res. 1980 Apr;14(4 Pt 1):304-7. doi: 10.1203/00006450-198004000-00009.
Plasma renin (PRC) and aldosterone concentrations are known to be high during early postnatal life. Whether this is related to the low rates of renal blood flow or to sodium homeostasis remains unknown. Measurement of PRC, renal blood flow, and its intrarenal distribution were performed in 1- to 3-wk-old puppies subjected to maneuvers known to stimulate or inhibit renin release. In the awake state, PRC was observed to be higher in 2-wk-old puppies than in older or younger dogs, (P less than 0.0001). Significant differences in PRC were also found between litters (P less than 0.0001), but they did not account for the age-related changes. Anesthesia resulted in a 3- to 5-fold rise in PRC, whereas saline expansion suppressed PRC at all ages, the fall tending to become progressively greater with age (P less than 0.09). There was no significant correlation between the age-related changes in PRC and those in renal blood flow or its intrarenal distribution. The results of these experiments demonstrate that in the newborn from a qualitative point of view, PRC changes appropriately in response to various stimuli. However, quantitative age-related differences exist in this regard, reflecting an initial immaturity of the feedback system.
已知出生后早期血浆肾素（PRC）和醛固酮浓度较高。这是否与肾血流量低或钠稳态有关仍不清楚。对1至3周龄的幼犬进行了PRC、肾血流量及其肾内分布的测量，这些幼犬接受了已知能刺激或抑制肾素释放的操作。在清醒状态下，观察到2周龄幼犬的PRC高于年龄较大或较小的犬（P<0.0001）。不同窝的幼犬之间PRC也存在显著差异（P<0.0001），但它们并不能解释与年龄相关的变化。麻醉导致PRC升高3至5倍，而生理盐水扩容在所有年龄段均抑制PRC，随着年龄增长，下降趋势逐渐增大（P<0.09）。PRC与年龄相关的变化与肾血流量及其肾内分布的变化之间无显著相关性。这些实验结果表明，从定性的角度来看，新生儿的PRC能对各种刺激做出适当变化。然而，在这方面存在与年龄相关的定量差异，反映出反馈系统最初的不成熟。
