Bocking A D, McMillen I C, Harding R, Thorburn G D
J Dev Physiol. 1986 Aug;8(4):237-45.
We have measured the changes in fetal and maternal plasma concentrations of cortisol in relation to blood gases and percent oxygen saturation during 2- and 4-h episodes of reversibly reduced uterine blood flow in sheep between 120 days gestation and term. During that period of reduced uterine blood flow there was a significant decrease in fetal arterial percent oxygen saturation (SaO2), PO2 and pH. Fetal SaO2 decreased from 59.5 +/- 3.2% to 31.8% +/- 2.8% by 15 min, 32.9 +/- 2.9% by 60 min, and 33.5 +/- 2.9% by 120 min. Fetal PO2 decreased from 3.2 +/- 0.1 KPa to 2.0 +/- 0.2 KPa by 15 min, 2.2 +/- 0.2 KPa by 60 min and 2.3 +/- 0.1 KPa by 120 min. Fetal pH decreased from 7.36 +/- 0.01 to 7.30 +/- 0.03 by 15 min, 7.27 +/- 0.02 by 60 min and 7.25 +/- 0.03 by 120 min. During the period of reduced uterine blood flow, fetal plasma concentrations of cortisol increased from 37.1 +/- 10.8 nmol/l to 53.3 +/- 9.2 nmol/l by 15 min, 49.2 +/- 11.4 nmol/l by 60 min and 43.3 +/- 9.0 nmol/l by 120 min. The greatest percentage increase in fetal plasma concentrations of cortisol occurred in fetuses of 126-139 days gestation. There was no significant change in maternal blood gases, SaO2 or plasma concentrations of cortisol. These experiments demonstrate that there is a significant increase in fetal plasma concentrations of cortisol in response to reductions in uterine blood flow from as early as 120 days gestation.
我们测定了妊娠120天至足月的绵羊在子宫血流可逆性减少2小时和4小时期间，胎儿和母体血浆皮质醇浓度与血气及氧饱和度百分比的变化。在子宫血流减少期间，胎儿动脉血氧饱和度百分比（SaO2）、PO2和pH值显著下降。胎儿SaO2在15分钟时从59.5±3.2%降至31.8%±2.8%，60分钟时降至32.9±2.9%，120分钟时降至33.5±2.9%。胎儿PO2在15分钟时从3.2±0.1千帕降至2.0±0.2千帕，60分钟时降至2.2±0.2千帕，120分钟时降至2.3±0.1千帕。胎儿pH值在15分钟时从7.36±0.01降至7.30±0.03，60分钟时降至7.27±0.02，120分钟时降至7.25±0.03。在子宫血流减少期间，胎儿血浆皮质醇浓度在15分钟时从37.1±10.8纳摩尔/升增至53.3±9.2纳摩尔/升，60分钟时增至49.2±11.4纳摩尔/升，120分钟时增至43.3±9.0纳摩尔/升。妊娠126 - 139天的胎儿血浆皮质醇浓度增加百分比最大。母体血气、SaO2或血浆皮质醇浓度无显著变化。这些实验表明，早在妊娠120天时，胎儿血浆皮质醇浓度就会因子宫血流减少而显著增加。
