应用双标水法对16名青年女性进行能量消耗的测定

目的研究建立以双标水为示踪剂测定我国人体能量代谢的方法。方法以16名20～25岁军校女学员为研究对象,按照0.25g2H2O/kg体重和0.18gH218O/kg体重的剂量给受试者服用国产双标水试剂,采用多点法收集受试者服用双标水前后14d内的尿样并进行质谱分析,根据公式计算得到受试者能量消耗的数据。结果质控盲样与平行样测量相对偏差2H为0.145%±0.049%,18O为0.123%±0.033%,尿样双复管测定的平均变异系数小于1%,根据质谱数据得到的同位素消除曲线线性关系良好,相关系数均大于0.99,且No与ND的比值在1.015～1.06之间,应用双标水法得到的受试者平均能量消耗为7.64±0.49MJ/d(1827.17±117.73kcal/d)。结论该方法测定结果可信度较高,适用于我国人体能量代谢的测定。

THE ENERGY EXPENDITURE DETERMINED BY THE DOUBLY LABELED WATER METHOD IN 16 YOUNG ADULT WOMEN

Objective To establish a method to estimate the energy expenditures of Chinese adults by using the doubly labeled water as tracer.Methods Sixteen Chinese female young adults aged from 20-25 years old were selected as the subjects.A mixed 2H218O dose containing 0.25g 2H2O/kg and 0.18g H218O/kg was given orally to each subject and urine specimens were collected before and after the isotope administration for 14d.Abundances of 2H and 18O in urine specimens were analyzed by using isotope-ratio mass spectrometry.The total energy expenditure of each subject was determined by calculation.Results The mean relative deviation between the unknown specimen and its parallel sample was 2H 0.145%± 0.049% and 18O 0.123%±0.033% respectively.The average coefficient of variance (CV) between the duplicate samples was less than 1%.The isotopic elimination curves had good linear relationship,and the No/ND ratio was within 1.015-1.06.The average energy expenditure measured by using the doubly labeled water method was 7.64±0.49MJ/d (1827.17±117.73kcal/d).Conclusion The method is accurate,and can be used for evaluation of the energy expenditures in Chinese adults.