Watson C S, White S E, Homan J, Abdollah S, Brien J F, Challis J R, Bocking A D
Department of Obstetrics and Gynecology, University of Western Ontario, Lawson Research Institute, St. Joseph's Health Centre, London, Canada.
Can J Physiol Pharmacol. 1996 Sep;74(9):1016-24.
When prolonged hypoxemia is induced in fetal sheep by reducing uterine blood flow, fetal breathing movements (FBM) return to normal incidence after their initial decrease. Ethanol also inhibits FBM. These experiments were designed to determine the role of fetal oxygenation status in affecting ethanol-induced inhibition of FBM. A 1-h maternal infusion of 1 g ethanol/kg maternal body weight was given to animals following 20 h of reduced uterine blood flow (RUBF; n = 9), as well as to normoxemic (n = 9) fetal sheep, and the effect on FBM, electrocortical activity (ECoG), and electroocular activity (EOG) was determined. In normoxemic fetuses, the incidence of FBM decreased from 26.1 +/- 5.5% to 2.8 +/- 1.6% (p < 0.05) with ethanol, subsequently returning to baseline values over 6 h, but there was no effect of ethanol on FBM incidence in RUBF fetuses (32.8 +/- 9.1%). Ethanol increased the incidence of intermediate ECoG from 16.6 +/- 2.9% to 49.0 +/- 9.8% (p < 0.01) in normoxemic fetuses, but there was no change in RUBF fetuses. We conclude that the adaptive mechanism(s) invoked by fetal sheep during prolonged RUBF abolishes its ability to respond behaviourally to ethanol.
通过减少子宫血流量在胎羊中诱发长时间低氧血症时，胎儿呼吸运动（FBM）在最初下降后会恢复到正常发生率。乙醇也会抑制FBM。这些实验旨在确定胎儿氧合状态在影响乙醇诱导的FBM抑制中的作用。在20小时子宫血流量减少（RUBF；n = 9）后，给动物静脉输注1 g乙醇/ kg母体体重1小时，同时也给正常氧合的（n = 9）胎羊输注，然后测定对FBM、皮层电图（ECoG）和眼电图（EOG）的影响。在正常氧合的胎儿中，乙醇使FBM发生率从26.1±5.5%降至2.8±1.6%（p < 0.05），随后在6小时内恢复到基线值，但乙醇对RUBF胎儿的FBM发生率没有影响（32.8±9.1%）。乙醇使正常氧合胎儿的中度ECoG发生率从16.6±2.9%增加到49.0±9.8%（p < 0.01），但RUBF胎儿没有变化。我们得出结论，胎羊在长时间RUBF期间调用的适应性机制消除了其对乙醇行为反应的能力。
