Junghans Peter, Larsson Caroline, Jensen Rasmus Bovbjerg, Tauson Anne-Helene
a Leibniz Institute for Farm Animal Biology, Institute of Nutritional Physiology 'Oskar Kellner' , Dummerstorf , Germany.
b Department of Veterinary Clinical and Animal Sciences, Faculty of Health and Medical Sciences , University of Copenhagen , Frederiksberg C , Denmark.
Isotopes Environ Health Stud. 2015;51(4):497-507. doi: 10.1080/10256016.2015.1110580.
We reconsider the principle of the (13)C bicarbonate (NaH(13)CO3) method ((13)C-BM) for the determination of the CO2 production to obtain an estimate of energy expenditure (EE). Its mathematical concept based on a three-compartmental model is related to the [(15)N]glycine end product method. The CO2 production calculated by the (13)C-BM, RaCO2((13)C) is compared to the result from the indirect calorimetry, RCO2(IC). In an interspecies comparison (dog, goat, horse, cattle, children, adult human; body mass ranging from 15 to 350 kg, resting and fasting conditions) we found an excellent correlation between the results of (13)C-BM and IC with RCO2(IC) = 0.703 × RaCO2((13)C), (R(2) = 0.99). The slope of this correlation corresponds to the fractional (13)C recovery (RF((13)C)) of (13)C in breath CO2 after administration of NaH(13)CO3. Significant increase in RF((13)C) was found in physically active dogs (0.95 ± 0.14; n = 5) vs. resting dogs (0.71 ± 0.10, n = 17; p = .015). The (13)C recovery in young bulls was greater in blood CO2 (0.81 ± 0.05) vs. breath CO2 (0.73 ± 0.05, n = 12, p < .001) and in ponies with oral (0.76 ± 0.03, n = 8) vs. intravenous administration of NaH(13)CO3 (0.69 ± 0.07; n = 8; p = .026). We suggest considering the (13)C-BM as a 'stand-alone' method to provide information on the total CO2 production as an index of EE.
我们重新审视了用于测定二氧化碳产生量以估算能量消耗(EE)的(13)C碳酸氢盐(NaH(13)CO3)法((13)C-BM)的原理。其基于三室模型的数学概念与[(15)N]甘氨酸终产物法相关。将通过(13)C-BM计算得出的二氧化碳产生量RaCO2((13)C)与间接量热法的结果RCO2(IC)进行比较。在种间比较(狗、山羊、马、牛、儿童、成年人;体重范围为15至350千克,处于静息和禁食状态)中,我们发现(13)C-BM和IC的结果之间具有极好的相关性,RCO2(IC)=0.703×RaCO2((13)C),(R(2)=0.99)。该相关性的斜率对应于给予NaH(13)CO3后呼出二氧化碳中(13)C的分数回收率(RF((13)C))。发现运动的狗(0.95±0.14;n=5)与静息的狗(0.71±0.10,n=17;p=0.015)相比,RF((13)C)显著增加。年轻公牛血液中二氧化碳的(13)C回收率(0.81±0.05)高于呼出二氧化碳中的回收率(0.73±0.05,n=12,p<0.001),口服NaH(13)CO3的小马(0.76±0.03,n=8)的回收率高于静脉注射NaH(13)CO3的小马(0.69±0.07;n=8;p=0.026)。我们建议将(13)C-BM视为一种“独立”方法,以提供关于总二氧化碳产生量的信息,作为能量消耗的指标。