1. From the Departments of Pharmacology (D.W.W., J.R.B., A.L.G.), Anesthesiology (J.R.B.), and Medicine (A.L.G.), Vanderbilt University School of Medicine, Nashville, Tenn, and the Department of Cardiovascular Medicine (N.M., A.K.), Hokkaido University Graduate School of Medicine, Sapporo, Japan.