DZHK (German Center for Cardiovascular Research), partner site Goettingen 3 articles published in JoVE Medicine Advanced Cardiac Rhythm Management by Applying Optogenetic Multi-Site Photostimulation in Murine Hearts Laura Diaz-Maue*1,2, Janna Steinebach*1, Michael Schwaerzle8,9, Stefan Luther1,3,4,6, Patrick Ruther8,9, Claudia Richter1,5,6,7 1Research Group Biomedical Physics, Max Planck Institute for Dynamics and Self-Organization, 2Research Electronics Department, Max Planck Institute for Dynamics and Self-Organization, 3Department of Pharmacology and Toxicology, University Medical Center Goettingen, 4Institute for Nonlinear Dynamics, Georg-August-University Goettingen, 5Department of Cardiology and Pneumology, University Medical Center Goettingen, 6German Center for Cardiovascular Research, DZHK e.V., partner site Goettingen, 7Laboratory Animal Science Unit, German Primate Center Leibniz Institute for Primate Research, 8Department of Microsystems Engineering (IMTEK), University of Freiburg, 9Cluster of Excellence BrainLinks-BrainTools, University of Freiburg This work reports a method for controlling the cardiac rhythm of intact murine hearts of transgenic channelrhodopsin-2 (ChR2) mice using local photostimulation with a micro-LED array and simultaneous optical mapping of epicardial membrane potential. Bioengineering Fibroblast Derived Human Engineered Connective Tissue for Screening Applications Gabriela L. Santos1,2, Tim Meyer1,2, Malte Tiburcy1,2, Alisa DeGrave1,2, Wolfram-Hubertus Zimmermann1,2,3,4,5, Susanne Lutz1,2 1Institute of Pharmacology and Toxicology, University Medical Center Goettingen, 2DZHK (German Center for Cardiovascular Research) partner site, Goettingen, 3Cluster of Excellence “Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells” (MBExC), University of Goettingen, 4Center for Neurodegenerative Diseases (DZNE), 5Fraunhofer Institute for Translational Medicine and Pharmacology (ITMP) Presented here is a protocol to generate engineered connective tissues for a parallel culture of 48 tissues in a multi-well plate with double poles, suitable for mechanistic studies, disease modeling, and screening applications. The protocol is compatible with fibroblasts from different organs and species and is exemplified here with human primary cardiac fibroblasts. Bioengineering Single-Cell Optical Action Potential Measurement in Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes Fitzwilliam Seibertz1,2, Martyn Reynolds3, Niels Voigt1,2,4 1Institute of Pharmacology and Toxicology, University Medical Center Goettingen, Goettingen, Germany, 2DZHK (German Center for Cardiovascular Research), Partner Site Goettingen, Germany, 3Cairn Research Ltd, Faversham, United Kingdom, 4Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Goettingen, Germany Here we describe optical acquisition and characterization of action potentials from induced pluripotent stem cell derived cardiomyocytes using a high-speed modular photometry system.