University Medical Center Utrecht, Utrecht University 1 article published in JoVE Biology Isolation of Cardiac and Vascular Smooth Muscle Cells from Adult, Juvenile, Larval and Embryonic Zebrafish for Electrophysiological Studies Soma S. Singareddy1, Conor McClenaghan1, Helen I. Roessler2, Robert Tryon1, Colin G. Nichols1 1Department of Cell Biology and Physiology and Center for the Investigation of Membrane Excitability Diseases, Washington University in St. Louis, 2Department of Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University The present protocol describes the acute isolation of viable cardiac and vascular smooth muscle cells from adult, juvenile, larval, and embryonic zebrafish (Danio rerio), suitable for electrophysiological studies.