Supramaniam V G, Jenkin G, Wallace E M, O'Connor A E, de Kretser D M, Miller S L
Department of Physiology, Monash University, Victoria, Australia.
Reprod Fertil Dev. 2004;16(6):625-32. doi: 10.1071/rd03110.
The aim of the present study was to determine whether activin A concentrations are dependent on feto-placental oxygen availability and to investigate the temporal relationship of activin A with prostaglandin (PG) E(2) and cortisol. Nine fetal sheep (six hypoxic and three control) were instrumented and catheterised at 0.8 gestation. Reduced uterine blood flow was used to achieve three levels of hypoxia (mild = fetal SaO(2) 40-50%; moderate = fetal SaO(2) 30-40%; severe = fetal SaO(2) 20-30%), for 4 h on 3 consecutive days. Activin A, PGE(2) and cortisol levels were determined in maternal and fetal blood and amniotic fluid. Moderate and severe hypoxia produced a significant (P < 0.05) increase in fetal plasma activin A concentrations. The amniotic fluid activin A concentrations were 15-fold higher than those in the fetal circulation, but were unchanged by hypoxia. The fetal PGE(2) response reflected the degree of hypoxia over the 3 days, with moderate and severe hypoxia producing a significant (P < 0.05) increase in PGE(2) concentrations. Fetal plasma cortisol concentrations were increased ( P < 0.05) during all levels of hypoxia. Fetal arterial activin A was increased in response to moderate and severe hypoxia, but levels were not maintained over the hypoxic period. The increases in activin A and cortisol concentrations preceded the increase in PGE(2).
本研究的目的是确定激活素A的浓度是否取决于胎儿-胎盘的氧供应情况，并研究激活素A与前列腺素（PG）E2和皮质醇之间的时间关系。9只胎羊（6只缺氧组和3只对照组）在妊娠0.8时进行仪器植入和插管。通过减少子宫血流量来实现三个缺氧水平（轻度=胎儿血氧饱和度40-50%；中度=胎儿血氧饱和度30-40%；重度=胎儿血氧饱和度20-30%），连续3天，每天4小时。测定母血、胎儿血和羊水中激活素A、PGE2和皮质醇的水平。中度和重度缺氧导致胎儿血浆激活素A浓度显著（P<0.05）升高。羊水中激活素A的浓度比胎儿循环中的浓度高15倍，但不受缺氧影响。胎儿PGE2的反应反映了3天内的缺氧程度，中度和重度缺氧导致PGE2浓度显著（P<0.05）升高。在所有缺氧水平下，胎儿血浆皮质醇浓度均升高（P<0.05）。胎儿动脉激活素A在中度和重度缺氧时升高，但在缺氧期间水平未维持。激活素A和皮质醇浓度的升高先于PGE2的升高。
