1. From the Department of Vascular Physiology (K.I., Y.A., T.S.), National Cardiovascular Center Research Institute, Osaka; the Department of Cardiovascular Medicine (K.I., T.K.), Graduate School of Medicine, Kyoto University; the Department of Physiological Chemistry and Metabolism (H.K.), Graduate School of Medicine, University of Tokyo; and the Department of Molecular Pathophysiology (T.S.), Graduate School of Pharmaceutical Sciences, Osaka University, Japan.