Sunehag A, Gustafsson J, Ewald U
Uppsala University Children's Hospital, Sweden.
Acta Paediatr. 1996 Nov;85(11):1339-43. doi: 10.1111/j.1651-2227.1996.tb13921.x.
The newborn infant must mobilize endogenous substrate stores to meet the requirements of glucose-dependent organs. High concentrations of free fatty acids and glycerol, and a rapid decrease in the respiratory quotient, indicate that lipids are an important fuel soon after birth. The purpose of the present study was to determine the onset of lipolysis and gluconeogenesis from glycerol in healthy, term, unfed infants. Eight infants were studied from a postnatal age of 3.5 +/- 0.5 h to 7.4 +/- 0.2 h using [6,6-2H2] glucose and [2-13C]glycerol analysed by gas chromatography/mass spectrometry. Plasma concentrations of glucose, glycerol and insulin averaged 2.9 +/- 0.4 mM, 369 +/- 89 microM and 9.4 +/- 9.4 +/- 3.7 microU.ml-1, respectively. The hepatic glucose production rate averaged 25.0 +/- 3.5 mumol.kg-1 min-1 (4.5 +/- 0.6 mg.kg-1.min-1) and the endogenous plasma appearance rate of glycerol 8.7 +/- 1.2 mumol.kg-1.min. On average, 57.9 +/- 8.4% of the glycerol was converted to glucose, representing 11.1 +/- 2.3% of hepatic glucose output. Thus, lipolysis and gluconeogenesis from glycerol are established within the first 8 h of life in term infants.
新生婴儿必须调动内源性底物储备，以满足依赖葡萄糖的器官的需求。高浓度的游离脂肪酸和甘油，以及呼吸商的迅速下降，表明脂质在出生后不久就是一种重要的燃料。本研究的目的是确定健康足月未喂养婴儿中甘油的脂肪分解和糖异生的起始时间。使用气相色谱/质谱分析的[6,6-2H2]葡萄糖和[2-13C]甘油，对8名婴儿从出生后3.5±0.5小时至7.4±0.2小时进行了研究。葡萄糖、甘油和胰岛素的血浆浓度分别平均为2.9±0.4 mM、369±89 microM和9.4±3.7 microU.ml-1。肝脏葡萄糖生成率平均为25.0±3.5 mumol.kg-1 min-1（4.5±0.6 mg.kg-1.min-1），甘油的内源性血浆出现率为8.7±1.2 mumol.kg-1.min。平均而言，57.9±8.4%的甘油转化为葡萄糖，占肝脏葡萄糖输出的11.1±2.3%。因此，足月婴儿在出生后的前8小时内就建立了甘油的脂肪分解和糖异生。
