1. From the Division of Cardiovascular Medicine (M.P., S.M., F.Y., A.D., A.J.M., S.S.S.), The Gill Heart Institute, University of Kentucky, Lexington; Carolina Cardiovascular Biology Center (M.R., C.E., C.V., S.S.S.), University of North Carolina, Chapel Hill; Department of Pharmacology (K.L.), University of Virginia, Charlottesville; Department of Molecular Biology (J.C.), The Scripps Research Institute, San Diego, Calif; and Department of Veterans Affairs Medical Center (S.S.S.), Lexington, Ky.