Exogenous nutrients do not diffuse throughout the body like a drop of dye in a beaker of water. Rather, they are allocated among tissues according to physiological rules determined by evolutionary history, physiological status, and environmental conditions. These rules also determine how endogenous nutrients are differentially mobilized and oxidized during the periods between meals. Metabolic tracers are emerging as powerful tools to address classic questions about the nutritional bioenergetics of animals. For example, which nutrients will be oxidized and which will be stored in the body? How are stored nutrients divided among the different organs and tissues? Which nutrients are mobilized between meals? When does an animal switch from one type of metabolic fuel to another? The answers to these questions surely differ among species, but also depend on complex interactions between the animal and its environment. Here I review the conceptual framework for using isotopically labeled tracers.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 61 • No. 3