Cellular Source of AF (IMAGE) University of Pennsylvania School of Medicine Caption Cardiac melanocyte-like cells in the mouse heart, identified by transgenic expression of a marker gene, are located in the region of the atria and the pulmonary veins and may serve as triggers for atrial arrhythmias. Credit Jon Epstein, MD, Vickas Patel, MD, PhD, University of Pennsylvania School of Medicine Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.