Alterations in fetal urine production during prolonged hypoxaemia induced by reduced uterine blood flow in sheep: Mechanisms

Abstract

1. Our aim was to identify mechanisms whereby prolonged fetal hypoxaemia alters renal function and urine production in fetal sheep. 2. Fetal hypoxaemia was induced for 24 h by reducing uterine blood flow at 129.0±2.1 days of gestation (term 145-147 days), causing a reduction in fetal arterial O2 saturation (SaO2) from 52.5±2.3 to 22.0±1.3% (P<0.05). This hypoxaemia was initially associated with a mild acidaemia (pH 7.23±0.03). 3. The glomerular filtration rate (GFR) increased from a control value of 1.8±0.3 mL/min per kg to a maximal value of 2.8±0.6 mL/min per kg (P<0.05) at 4-5 h of hypoxaemia, returning to control levels by 6-9 h of hypoxaemia. After 4 h of hypoxaemia renal blood flow was..