1. From the Department of Physiology and Cell Biology (A.V.G., L.T.H., B.J.H., G.E.B., V.V.F), College of Veterinary Medicine (A.P.-T., P.V.-P., R.L.H.), Division of Cardiovascular Medicine (R.W.), and College of Pharmacy (C.A.C.), College of Medicine, Dorothy M. Davis Heart and Lung Research Institute, Ohio State University, Columbus, OH.