Bell R C, Lanou A J, Frongillo E A, Levitsky D A, Campbell T C
Department of Medicine, University of Alberta, Edmonton, Canada.
Physiol Behav. 1994 Oct;56(4):767-73. doi: 10.1016/0031-9384(94)90240-2.
Total body electrical conductivity (TOBEC) has been promoted as a noninvasive method to estimate body composition in small mammals. Validation of this method has primarily been under normative conditions and has generally been inadequate. This article reports on the reliability and accuracy of TOBEC methodology to assess gradual, physiologically induced changes in body composition in rats under different experimental conditions. Reliability of the index of electrical conductivity (EM number) was assessed by analyzing components of variance. Accuracy was assessed by comparing EM number to actual lean body mass (LBM, from carcass analysis), across different experimental conditions, within a particular experimental condition, and over time for a given set of animals. Reliable measurements were obtained by strictly adhering to a standard protocol. TOBEC was inaccurate across experimental conditions, within experimental conditions, and within a single experimental condition during the course of an experiment. This inaccuracy apparently stemmed from the lack of a direct relationship between EM number and LBM; EM number was more strongly correlated with body weight than with LBM. At the present time, TOBEC cannot be used in place of carcass analysis to accurately predict the body composition of rats during or following the administration of a variety of experimental conditions.
总体电导率（TOBEC）已被推崇为一种估计小型哺乳动物身体成分的非侵入性方法。该方法的验证主要是在标准条件下进行的，且通常并不充分。本文报告了TOBEC方法在不同实验条件下评估大鼠身体成分逐渐发生的、生理诱导变化的可靠性和准确性。通过分析方差成分评估电导率指数（EM数）的可靠性。通过在不同实验条件下、特定实验条件内以及对给定一组动物随时间比较EM数与实际去脂体重（LBM，来自胴体分析）来评估准确性。通过严格遵守标准方案获得可靠的测量结果。在实验条件之间、实验条件内以及单个实验条件的实验过程中，TOBEC都是不准确的。这种不准确显然源于EM数与LBM之间缺乏直接关系；EM数与体重的相关性比与LBM的相关性更强。目前，在各种实验条件期间或之后，TOBEC不能替代胴体分析来准确预测大鼠的身体成分。
