Using isotope tracers to study metabolism: application in mouse models.

The application of isotope tracers for investigating metabolism in mice is discussed. To familiarize the reader, some basic principles regarding the use of tracer methods are outlined. Emphasis is placed on showing how investigators are using isotope tracers to study the regulation of carbohydrate, fat and/or protein turnover in vivo. Finally, some of the advantages of using labeled water (i.e., 2H(2)O and/or H(2)18O) to trace the kinetics of biological processes are considered. The background provided in this report should assist engineers in designing studies that enhance our understanding of conditions in which metabolism is altered (e.g., diabetes, cancer cachexia, failure to thrive and travel at zero-gravity).