1. From the Department of Molecular and Cellular Pharmacology (M.S.T., P.A., L.Y., K.A.W., N.H.B.), University of Miami, Fla; Departments of Cardiology and Medical Biochemistry (M.S.T., P.E.M., W.H.E.), Wales Heart Research Institute, University of Wales College of Medicine, Heath Park, Cardiff, UK; Department of Cardiology (G.A.H.), South West Cardiothoracic Centre, Plymouth, UK.