Junghans Peter, Görs Solvig, Langhammer Martina, Metges Cornelia C
a Institute of Nutritional Physiology 'Oskar Kellner', Leibniz Institute for Farm Animal Biology (FBN) , Dummerstorf , Germany.
b Institute of Genetics and Biometry, Leibniz Institute for Farm Animal Biology (FBN) , Dummerstorf , Germany.
Isotopes Environ Health Stud. 2018 Dec;54(6):561-572. doi: 10.1080/10256016.2018.1531855. Epub 2018 Oct 15.
We explored a novel doubly labelled water (DLW) method based on breath water (BW-DLW) in mice to determine whole body CO production and energy expenditure noninvasively. The BW-DLW method was compared to the DLW based on blood plasma. Mice (n = 11, 43.5 ± 4.6 g body mass (BM)) were administered orally a single bolus of doubly labelled water (1.2 g HO kg BM and 0.4 g HO kg BM, 99 atom% (AP) O or H). To sample breath water, the mice were placed into a respiration vessel. The exhaled water vapour was condensed in a cold-trap. The isotope enrichments of breath water were compared with plasma samples. The H/H and O/O isotope ratios were measured by means of isotope ratio mass spectrometry. The CO production (RCO) was calculated from the H and O enrichments in breath water and plasma over 5 days. The isotope enrichments of breath water vs. plasma were correlated (R = 0.89 for H and 0.95 for O) linearly. The RCO determined based on breath water and plasma was not different (113.2 ± 12.7 vs. 111.4 ± 11.0 mmol d), respectively. In conclusion, the novel BW-DLW method is appropriate to obtain reliable estimates of RCO avoiding blood sampling.
我们在小鼠中探索了一种基于呼出气水的新型双标记水（BW-DLW）方法，以无创地测定全身一氧化碳产生量和能量消耗。将BW-DLW方法与基于血浆的双标记水（DLW）方法进行了比较。给小鼠（n = 11，体重（BM）为43.5±4.6 g）口服单次大剂量的双标记水（1.2 g H₂¹⁸O/kg BM和0.4 g H₂³H/kg BM，99原子%（AP）的¹⁸O或³H）。为了采集呼出气水，将小鼠放入呼吸容器中。呼出的水蒸气在冷阱中冷凝。将呼出气水的同位素丰度与血浆样本进行比较。通过同位素比率质谱法测量H/³H和¹⁸O/¹⁶O同位素比率。根据5天内呼出气水和血浆中H和¹⁸O的丰度计算一氧化碳产生量（RCO）。呼出气水与血浆的同位素丰度呈线性相关（H的R = 0.89，¹⁸O的R = 0.95）。基于呼出气水和血浆测定的RCO没有差异（分别为113.2±12.7和111.4±11.0 mmol/d）。总之，新型BW-DLW方法适合在避免采血的情况下获得可靠的RCO估计值。
