Robillard J E, Weitzman R E, Burmeister L, Smith F G
Circ Res. 1981 Jan;48(1):128-38. doi: 10.1161/01.res.48.1.128.
The effects of fetal hypoxemia on renal hemodynamics and renal function were studied in two groups of chronically catheterized young (< 120 days of gestation) and near-term lamb fetuses (> 130 days). Fetal hypoxemia produced, in both groups, a significantly decrease in renal blood flow (RBF) and a significant increase in the filtration fraction. However, the glomerular filtration rate (GFR) did not change significantly suggesting that the renal vasoconstriction associated with fetal hypoxemia was more important at the efferent than at the afferent arteriolar level. In the group of near-term fetuses, the decrease in RBF correlated closely with changes in plasma renin activity (PRA) (r = 0.77). No changes in PRA were observed during hypoxemia in the group of young fetuses. After hypoxemia, reactive hyperemia associated with a significant increase in urinary prostaglandin excretion (PGE and PGF2 alpha) was observed in near-term fetuses but not in young fetuses. It also was demonstrated that fetal hypoxemia produced a significant increase in fetal plasma concentrations of vasopressin associated with an antidiuresis in all but one near-term fetus and in 50% of the young fetuses, suggesting that the ability of the fetal kidney to reabsorb free water is more developed in near-term fetuses. Finally, fetal hypoxemia had no effect on mean arterial pressure and heart rate in young fetuses; however, in near-term fetuses, a significant increase in blood pressure and a decrease in heart rate were observed. In summary, it appears that the response of the fetal kidney to hypoxemia depends on the degree of fetal maturation.
在两组长期插管的年轻（妊娠<120天）和近足月羔羊胎儿（>130天）中研究了胎儿低氧血症对肾血流动力学和肾功能的影响。两组胎儿低氧血症均导致肾血流量（RBF）显著降低，滤过分数显著升高。然而，肾小球滤过率（GFR）没有显著变化，这表明与胎儿低氧血症相关的肾血管收缩在出球小动脉水平比在入球小动脉水平更重要。在近足月胎儿组中，RBF的降低与血浆肾素活性（PRA）的变化密切相关（r = 0.77）。在年轻胎儿组低氧血症期间未观察到PRA的变化。低氧血症后，在近足月胎儿中观察到与尿前列腺素排泄（PGE和PGF2α）显著增加相关的反应性充血，但在年轻胎儿中未观察到。还证明胎儿低氧血症使胎儿血浆血管加压素浓度显著升高，除一只近足月胎儿外，所有近足月胎儿和50%的年轻胎儿均出现抗利尿，这表明近足月胎儿的胎儿肾脏重吸收自由水的能力更发达。最后，胎儿低氧血症对年轻胎儿的平均动脉压和心率没有影响；然而，在近足月胎儿中，观察到血压显著升高和心率降低。总之，胎儿肾脏对低氧血症的反应似乎取决于胎儿成熟程度。
