Evain-Brion D
Laboratoire de Physiopathologie du Développement, ENS, Paris, France.
Horm Res. 1994;42(4-5):207-14. doi: 10.1159/000184195.
The regulation of fetal growth is complex and poorly known. During the first trimester of pregnancy, no strict endocrine mechanisms are involved, but embryonic growth might be controlled at the level of the individual organs by supply of nutrients and by locally active growth factors. Later on, fetal growth depends essentially upon the maternoplacental cooperation in delivering nutrients to the fetus. Therefore, the major role of hormones in fetal growth is to mediate the utilization of available substrate. In late gestation, placental size and fetal growth rate are well correlated, pointing to a key role of the placenta in the regulation of fetal growth. It is therefore important to understand the molecular mechanisms involved in regulating placental development and endocrine functions. TGF alpha and EGF might play major roles as suggested by the modulation of their receptors with placental development, and by the specific alterations of EGF receptors in intrauterine growth retardation. In addition, human placenta specifically secretes placental growth hormone, the level of which is significantly decreased in the sera of pregnant women bearing a fetus with intrauterine growth retardation.
胎儿生长的调节机制复杂且鲜为人知。在妊娠的前三个月，不涉及严格的内分泌机制，但胚胎生长可能通过营养物质供应和局部活性生长因子在各个器官水平上受到控制。随后，胎儿生长主要依赖于母胎胎盘在向胎儿输送营养物质方面的协同作用。因此，激素在胎儿生长中的主要作用是介导可用底物的利用。在妊娠晚期，胎盘大小与胎儿生长速率密切相关，这表明胎盘在调节胎儿生长中起关键作用。因此，了解调节胎盘发育和内分泌功能的分子机制很重要。转化生长因子α（TGFα）和表皮生长因子（EGF）可能起主要作用，这是根据它们的受体随胎盘发育的调节以及宫内生长迟缓时EGF受体的特异性改变所表明的。此外，人胎盘特异性分泌胎盘生长激素，怀有宫内生长迟缓胎儿的孕妇血清中该激素水平显著降低。
