DESCRIPTION (provided by applicant): There are three specific aims of the project, which are to (a) develop a methodology for metabolic flux estimation based on nonstationary isotopic tracer experiments, (b) create a general-purpose software application for analysis and interpretation of nonstationary isotopic tracer experiments, and (c) to apply the aforementioned theoretical results and software tools to analyze hepatocyte metabolism under diabetic and normal conditions. This research will provide a deeper understanding of the mechanisms by which the liver responds to diabetic disease states, thus leading to novel strategies for disease treatment, monitoring, and diagnosis. By allowing tracer studies to be performed during the transient period preceding isotopic steadystate, the techniques developed in this project will permit flux estimates to be obtained within a shorter timeframe than traditional methods. Because the liver-specific functions of hepatocytes often degrade over time, it is important to analyze these cells soon after they are isolated from the liver to get an accurate picture of the in vivo flux state.