Wang ZiMian, St-Onge Marie-Pierre, Lecumberri Beatriz, Pi-Sunyer F Xavier, Heshka Stanley, Wang Jack, Kotler Donald P, Gallagher Dympna, Wielopolski Lucian, Pierson Richard N, Heymsfield Steven B
Weight Control Unit, Obesity Research Center, St. Luke's-Roosevelt Hospital, Columbia University College of Physicians and Surgeons, 1090 Amsterdam Avenue, 14th Floor, New York, NY 10025, USA.
Am J Physiol Endocrinol Metab. 2004 Jan;286(1):E123-8. doi: 10.1152/ajpendo.00227.2003. Epub 2003 Oct 7.
Existing models to estimate the metabolically active body cell mass (BCM) component in vivo remain incompletely developed. The classic Moore model is based on an assumed BCM potassium content of 120 mmol/kg. Our objectives were to develop an improved total body potassium (TBK)-independent BCM prediction model on the basis of an earlier model (Cohn SH, Vaswani AN, Yasumura S, Yuen K, and Ellis KJ. J Lab Clin Med 105: 305-311, 1985), to apply this improved model in subjects to explore the sex and age dependence of the TBK/BCM ratio, to develop a new TBK/BCM model on the basis of physiological associations between TBK and total body water (TBW) at the cellular level of body composition, and to fit this new model with available reference data. Subjects were 112 healthy adults who had the following components measured: TBW by 2H2O or 3H2O, extracellular water by NaBr, total body nitrogen by in vivo neutron activation, bone mineral by dual-energy X-ray absorptiometry, and TBK by whole body counting. Human reference data were collected from earlier published reports. The improved Cohn model-derived TBK/BCM ratio was (mean +/- SD) 109.0 +/- 10.9 mmol/kg and was not significantly related to sex and age. A simplified version of the new TBK-TBW model provided a TBK/BCM ratio almost identical (109.1 mmol/kg) to that derived by the improved Cohn model. The TBK-BCM prediction formula derived from the improved and new models [BCM (kg) = 1/109 x TBK (mmol); or BCM = 0.0092 x TBK] gives BCM estimates approximately 11% higher than the classic Moore model (BCM = 0.0083 x TBK) formulated on rough tissue composition estimates. The present analyses provide a physiologically based, improved, and validated TBK-BCM prediction formula that should prove useful in body composition and metabolism research.
现有的用于体内估计代谢活跃身体细胞质量（BCM）成分的模型仍未完全完善。经典的摩尔模型基于假设的BCM钾含量为120 mmol/kg。我们的目标是在早期模型（Cohn SH、Vaswani AN、Yasumura S、Yuen K和Ellis KJ。《实验室与临床医学杂志》105: 305 - 311, 1985）的基础上开发一种改进的、独立于总体钾（TBK）的BCM预测模型，将此改进模型应用于受试者以探究TBK/BCM比值的性别和年龄依赖性，基于身体成分细胞水平上TBK与总体水（TBW）之间的生理关联开发一种新的TBK/BCM模型，并将此新模型与可用的参考数据进行拟合。受试者为112名健康成年人，对其进行了以下成分的测量：通过2H2O或3H2O测量TBW，通过NaBr测量细胞外液，通过体内中子活化测量总体氮，通过双能X射线吸收法测量骨矿物质，以及通过全身计数测量TBK。人类参考数据从早期发表的报告中收集。改进的源自科恩模型的TBK/BCM比值为（均值±标准差）109.0±10.9 mmol/kg，且与性别和年龄无显著相关性。新的TBK - TBW模型的简化版本提供的TBK/BCM比值（109.1 mmol/kg）与改进的科恩模型得出的比值几乎相同。源自改进模型和新模型的TBK - BCM预测公式[BCM（kg）= 1/109×TBK（mmol）；或BCM = 0.0092×TBK]得出的BCM估计值比基于粗略组织成分估计制定的经典摩尔模型（BCM = 0.0083×TBK）高出约11%。目前的分析提供了一个基于生理学的、改进的且经过验证的TBK - BCM预测公式，该公式在身体成分和代谢研究中应会被证明是有用的。
