caa a22 4500 38809768X CHVBK 20180307125308.0 cr unu---uuuuu 161130e199911 xx s 000 0 eng 10.1017/S0029665199001263 doi S0029665199001263 pii (NATIONALLICENCE)cambridge-10.1017/S0029665199001263 Coggan Andrew R. Biomedical Mass Spectrometry Facility, University of Maryland School of Medicine, Department of Medicine, Division of Gerontology, VA Medical Center (BT18GR), 10 N Greene Street, Baltimore, MD 21201, USA Use of stable isotopes to study carbohydrate and fat metabolism at the whole-body level [Elektronische Daten] [Andrew R. Coggan] The present review discusses the advantages and limitations of using stable-isotope tracers to assess carbohydrate and fat metabolism at the whole-body level. One advantage of stable-(v. radioactive-) isotope tracers is the relative ease with which the location of a label within a molecule can be determined using selected-ion-monitoring GC-mass spectrometry (SIM-GC- MS). This technique minimizes potential problems due to label recycling, allows the use of multiple-labelled compounds simultaneously (e.g. to quantify glucose cycling), and perhaps most importantly, has led to the development of unique stable-isotope methods for, for example, quantifying gluconeogenesis. However, the limited sensitivity of SIM-GC-MS sometimes requires that relatively large amounts of a stable-isotope tracer be used, thus increasing cost and potentially altering metabolism. At least theoretically, stable- (or radioactive-) isotope tracers can also be used in conjunction with indirect calorimetry to estimate utilization of muscle glycogen or triacylglycerol stores, thus potentially circumventing the need to obtain muscle biopsies. These calculations, however, require certain critical assumptions, which if incorrect could lead to major errors in the values obtained. Despite such limitations, stable-isotope tracers provide a powerful and sometimes unique tool for investigating carbohydrate and fat metabolism at the whole-body level. With continuing advances in availability, instrumentation and methods, it is likely that stable-isotope tracers will become increasingly important in the immediate future. The Nutrition Society Stable-isotope tracers nationallicence Exercise nationallicence Lipolysis nationallicence Proceedings of the Nutrition Society Cambridge University Press 58/4(1999-11), 953-961 0029-6651 58:4<953 1999 58 PNS https://doi.org/10.1017/S0029665199001263 text/html Onlinezugriff via DOI 1 conference jats NATIONALLICENCE 856 40 https://doi.org/10.1017/S0029665199001263 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Coggan Andrew R. Biomedical Mass Spectrometry Facility, University of Maryland School of Medicine, Department of Medicine, Division of Gerontology, VA Medical Center (BT18GR), 10 N Greene Street, Baltimore, MD 21201, USA NATIONALLICENCE 773 0- Proceedings of the Nutrition Society Cambridge University Press 58/4(1999-11), 953-961 0029-6651 58:4<953 1999 58 PNS CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge