Ertl T, Funke S, Sárkány I, Szabó I, Rascher W, Blum W F, Sulyok E
Department of Obstetrics and Gynecology, Medical University of Pécs, Hungary.
Biol Neonate. 1999 Mar;75(3):167-76. doi: 10.1159/000014093.
The present study was carried out to investigate leptin levels in arterial and venous cord serum and in amniotic fluid in full-term infants at birth and on the 5th postnatal day to define the relationship of leptin to intrauterine growth rate, gender and early postnatal life. The relation of weight gain to serum leptin levels in male preterm infants was determined measuring leptin concentration weekly in the first 5 postnatal weeks. Testosterone levels were determined simultaneously to explore a possible relationship between leptin and testosterone concentrations. Fifty-three term newborn infants with mean birth weight and gestational age of 3,419 g (range 2,150-4,480) and 38.9 weeks (range 36-41) and 19 preterm male infants (mean birth weight and gestational age were 1,416 g (770-1,800) and 30.2 weeks (26-35) were enrolled into the study. Leptin and testosterone levels were determined by radioimmunoassay. It was demonstrated that serum leptin levels were markedly elevated in the cord blood without discernible arteriovenous differences. Cord blood leptin was found to correlate with birth weight (r = 0.40, p < 0.002), weight to length ratio (r = 0.40, p < 0.002) and body mass index (r = 0.35, p < 0.005). It was significantly lower in boys as opposed to girls (p < 0.01) and there was an apparent fall by the 5th postnatal day (p < 0.001). Amniotic fluid contained leptin in much less concentration than cord blood and it proved to be independent of intrauterine growth or gender. Serum leptin concentration in preterm infants at 1 week of age was significantly lower compared with term infants (p < 0.002) and it increased progressively with age (p < 0.01). An inverse relationship was found between leptin and testosterone level (r = -0.358, p < 0.01) and a positive correlation between leptin level and weight/height ratio (r = 0.674, p < 0.01). It is concluded that leptin derived either from placenta or fetal adipose tissue may be involved in regulating fetal growth and development and it may be related to energy intake, storage and expenditure. In preterm male infants serum leptin concentration increases with postnatal weight and testosterone may suppress leptin synthesis.
本研究旨在调查足月婴儿出生时及出生后第5天动脉和静脉脐血以及羊水中的瘦素水平，以确定瘦素与宫内生长速率、性别及出生后早期生活的关系。通过在出生后前5周每周测量瘦素浓度，确定了男性早产儿体重增加与血清瘦素水平的关系。同时测定睾酮水平，以探讨瘦素与睾酮浓度之间可能存在的关系。53名足月新生儿平均出生体重为3419g（范围2150 - 4480g），平均孕周为38.9周（范围36 - 41周），以及19名男性早产儿（平均出生体重和孕周分别为1416g（770 - 1800g）和30.2周（26 - 35周））被纳入研究。瘦素和睾酮水平通过放射免疫测定法测定。结果表明，脐血中血清瘦素水平显著升高，且无明显动静脉差异。发现脐血瘦素与出生体重（r = 0.40，p < 0.002）、体重与身长比（r = 0.40，p < 0.002）和体重指数（r = 0.35，p < 0.005）相关。男孩的瘦素水平明显低于女孩（p < 0.01），且出生后第5天明显下降（p < 0.001）。羊水中瘦素浓度远低于脐血，且与宫内生长或性别无关。1周龄早产儿的血清瘦素浓度明显低于足月儿（p < 0.002），且随年龄逐渐升高（p < 0.01）。发现瘦素与睾酮水平呈负相关（r = -0.358，p < 0.01），瘦素水平与体重/身高比呈正相关（r = 0.674，p < 0.01）。结论是，来自胎盘或胎儿脂肪组织的瘦素可能参与调节胎儿生长发育，且可能与能量摄入、储存和消耗有关。在男性早产儿中，血清瘦素浓度随出生后体重增加而升高，睾酮可能抑制瘦素合成。
