Wintour E M, Coghlan J P, Towstoless M
J Endocrinol. 1985 Aug;106(2):R13-5. doi: 10.1677/joe.0.106r013.
Cortisol was infused, intravenously, for 4 h continuously into 5 chronically cannulated ovine fetuses at 111-120 days of gestation (term is 142-152 days). The dose used was 100 micrograms/h, and raised fetal blood cortisol concentrations from 8.2 +/- 4.0 to 56.5 +/- 19.0 nmol/l (values are mean +/- SEM). The effects observed were a 4-5 fold increase in sodium and chloride excretion, a doubling of potassium excretion and free water clearance, no significant changes in urine pH, urea and creatinine excretions, and an increase in urine osmolality from 129 +/- 7.5 to 154.4 +/- 11.3 mosmol/kg water. There were no significant changes in any of the measured parameters in 5 fetuses infused with 0.9% NaCl for 4h. It is suggested that the hyponatremia and inability to retain sodium observed in many premature or very low birth weight babies may be due to the fact that their kidneys are behaving as fetal rather than neonatal organs and responding to the high plasma cortisol concentrations found in such babies with a natriuresis.
在妊娠111 - 120天（足月为142 - 152天）时，对5只长期插管的绵羊胎儿静脉持续输注皮质醇4小时。所用剂量为100微克/小时，使胎儿血皮质醇浓度从8.2±4.0纳摩尔/升升至56.5±19.0纳摩尔/升（数值为均值±标准误）。观察到的效应为钠和氯排泄增加4 - 5倍，钾排泄和自由水清除率加倍，尿液pH值、尿素和肌酐排泄无显著变化，尿渗透压从129±7.5毫渗摩尔/千克水增至154.4±11.3毫渗摩尔/千克水。对5只输注0.9%氯化钠4小时的胎儿，所测参数均无显著变化。提示许多早产儿或极低出生体重儿出现的低钠血症及不能保留钠的情况，可能是由于他们的肾脏表现为胎儿而非新生儿器官，并且对这些婴儿中发现的高血浆皮质醇浓度产生利尿排钠反应。
