Ehrhardt Richard A, Bell Alan W, Boisclair Yves R
Department of Animal Science, Cornell University, Ithaca, New York 14853, USA.
Am J Physiol Regul Integr Comp Physiol. 2002 Jun;282(6):R1628-35. doi: 10.1152/ajpregu.00750.2001.
To better understand the biology of leptin during prenatal life, the developmental and spatial regulation of leptin was studied in ovine fetuses. Fetal plasma leptin increased steadily between days 40 and 143 postcoitus (PC), but it was unrelated to fetal weight or placental weight at day 135 PC. Leptin gene expression was detected in fetal brain and liver during most of gestation and in fetal adipose tissue after day 100 PC. At day 130 PC, expression in fetal perirenal adipose tissue was approximately 10% of maternal expression. In contrast, leptin gene expression was never detected in the placenta and other uteroplacental tissues. When ewes were fed 55% of requirements between days 122 and 135 PC, fetal plasma leptin remained constant despite acute reduction in maternal concentration. We conclude that fetal plasma leptin originates mostly from nonadipose tissue in early pregnancy and, in addition, from fetal adipose tissue near term. The role of fetal plasma leptin remains uncertain given the lack of nutritional regulation and association with fetal growth.
为了更好地了解孕期瘦素的生物学特性，对绵羊胎儿瘦素的发育及空间调节进行了研究。在交配后40天至143天（PC）期间，胎儿血浆瘦素稳步增加，但在妊娠135天时，其与胎儿体重或胎盘重量无关。在妊娠的大部分时间里，胎儿大脑和肝脏中均可检测到瘦素基因表达，在妊娠100天后，胎儿脂肪组织中也可检测到。在妊娠130天时，胎儿肾周脂肪组织中的表达约为母体表达的10%。相比之下，在胎盘和其他子宫胎盘组织中从未检测到瘦素基因表达。当母羊在妊娠122天至135天期间的进食量为需求量的55%时，尽管母体瘦素浓度急剧下降，但胎儿血浆瘦素仍保持恒定。我们得出结论，妊娠早期胎儿血浆瘦素主要来源于非脂肪组织，此外，足月时还来源于胎儿脂肪组织。鉴于缺乏营养调节以及与胎儿生长缺乏关联，胎儿血浆瘦素的作用仍不确定。
