Studies were approved by Institutional Animal Care and Use Committees (The Scripps Research Institute and University of California, San Diego). Plg-RKT gene targeted mice (31 (link)) were backcrossed ten generations into the C57Bl/6J background. Beginning at 8–10 weeks of age, male Plg-RKT−/− mice and Plg-RKT-+/+ littermates were placed on a HFD (D12492, 60% kcals from fat, Research Diets, New Brunswick NJ) or control low fat diet (LFD,D12450J, 10 kcal % fat, matching sucrose to D12492, Research Diets). Body weights were obtained weekly.