1. From the Department of Pharmacology and Toxicology (L.L., G.D.F., S.W.W., C.A.N., J.J.G, A.F.C.) and the Neuroscience Program (G.D.F., J.J.G, A.F.C.), Michigan State University, East Lansing; and the Hypertension and Vascular Research Division (P.J.P.), Henry Ford Hospital, Detroit, Mich.