University of Ottawa Heart Institute 2 articles published in JoVE Biology Viral Transgene Expression in Rodent Hearts and the Assessment of Cardiac Arrhythmia Risk Aizhu Lu1,2, Jerry Wang1,2, Ying Xia1,2, Ruonan Gu1, Kyoung-Han Kim1,2, Erin E. Mulvihill1,3, Darryl R. Davis1,2, Rob S. Beanlands1, Wenbin Liang1,2 1University of Ottawa Heart Institute, 2Department of Cellular and Molecular Medicine, University of Ottawa, 3Department of Biochemistry, Microbiology and Immunology, University of Ottawa The present protocol describes methods for transgene expression in rat and mouse hearts by direct intramyocardial injection of the virus under echocardiography guidance. Methods for the assessment of the susceptibility of hearts to ventricular arrhythmias by the programmed electrical stimulation of isolated, Langendorff-perfused hearts are also explained here. Biology Assessment of the Metabolic Effects of Isocaloric 2:1 Intermittent Fasting in Mice Ri Youn Kim*1,2, Ju Hee Lee*3,4, Yena Oh1,2, Hoon-Ki Sung3,4,5, Kyoung-Han Kim1,2 1University of Ottawa Heart Institute, 2Department of Cellular and Molecular Medicine, University of Ottawa, 3Translational Medicine Program, The Hospital for Sick Children, 4Department of Laboratory Medicine and Pathobiology, University of Toronto, 5Banting and Best Diabetes Centre, University of Toronto The current article describes a detailed protocol for isocaloric 2:1 intermittent fasting to protect and treat against obesity and impaired glucose metabolism in wild-type and ob/ob mice.