Coulter C L, Giraud A S, Hooper S B, Parker L, McMillen I C
Department of Physiology, Monash University, Clayton, Victoria, Australia.
J Dev Physiol. 1990 Nov;14(5):267-72.
We have investigated whether enkephalin-containing peptides and catecholamines are increased in fetal plasma during periods of reduced uterine blood flow which produce moderate fetal asphyxia (i.e. hypoxemia, hypercapnia and acidemia). Experiments (n = 16) were performed in 11 ewes between 121-139 days gestation. In 8 experiments a clamp placed around the common iliac artery of the ewe was adjusted to produce a 50% reduction in the partial pressure of arterial oxygen (PO2) in fetal plasma for 30 min between 121-125 days gestation (n = 4) and between 131-139 days gestation (n = 4). Control (n = 8) experiments were performed when the arterial clamp was not adjusted. There was no significant effect of asphyxia on fetal plasma noradrenaline concentrations before 126 days gestation. After 130 days gestation during asphyxia, fetal plasma noradrenaline concentrations increased significantly from 2.20 +/- 0.72 pmol/ml (-15 min) to 14.06 +/- 0.75 pmol/ml (+5 min). The fetal adrenaline response to asphyxia did not change with increasing gestational age and after 130 days gestation fetal plasma adrenaline increased significantly from 1.48 +/- 0.46 pmol/ml (-15 min) to 4.05 +/- 1.22 pmol/ml (+10 min). Met-enkephalin-arg6-phe7 immunoreactivity was measurable (25-117 pg/ml) in all pre-experimental fetal sheep plasma samples collected between 121-139 days gestation. There was no specific effect of asphyxia on fetal plasma [Met]-enkephalin-arg6-phe7-IR before 130 days gestation. However after 130 days gestation, there was a significant increase in fetal plasma (Met-enkephalin Arg-6-phe7-IR above baseline values, when compared to control experiments.(ABSTRACT TRUNCATED AT 250 WORDS)
我们研究了在导致中度胎儿窒息（即低氧血症、高碳酸血症和酸血症）的子宫血流减少期间，胎儿血浆中含脑啡肽的肽类和儿茶酚胺是否增加。在11只妊娠121 - 139天的母羊身上进行了实验（n = 16）。在8个实验中，在妊娠121 - 125天（n = 4）和131 - 139天（n = 4）之间，调整置于母羊髂总动脉周围的夹子，使胎儿血浆中的动脉血氧分压（PO2）降低50%，持续30分钟。当不调整动脉夹子时进行对照实验（n = 8）。在妊娠126天之前，窒息对胎儿血浆去甲肾上腺素浓度没有显著影响。在妊娠130天之后的窒息期间，胎儿血浆去甲肾上腺素浓度从2.20±0.72 pmol/ml（-15分钟）显著增加到14.06±0.75 pmol/ml（+5分钟）。胎儿肾上腺素对窒息的反应不随胎龄增加而变化，在妊娠130天之后，胎儿血浆肾上腺素从1.48±0.46 pmol/ml（-15分钟）显著增加到4.05±1.22 pmol/ml（+10分钟）。在妊娠121 - 139天收集的所有实验前胎儿绵羊血浆样本中均可检测到甲硫氨酸脑啡肽 - 精氨酸6 - 苯丙氨酸7免疫反应性（25 - 117 pg/ml）。在妊娠130天之前，窒息对胎儿血浆[甲硫氨酸] - 脑啡肽 - 精氨酸6 - 苯丙氨酸7 - IR没有特异性影响。然而，在妊娠130天之后，与对照实验相比，胎儿血浆（甲硫氨酸脑啡肽 - 精氨酸6 - 苯丙氨酸7 - IR）高于基线值显著增加。（摘要截断于250字）
