Robarts Research Institute and the Department of Physiology and Pharmacology, University of Western Ontario, London, Canada (A.Z., M.S., M.S.M.L., S.F., D.G.W.).
Hotchkiss Brain Institute, Libin Cardiovascular Institute and the Department of Physiology and Pharmacology, University of Calgary, Alberta, Canada (C.H.T.T., U.I.T., G.R.J.G., D.G.W.).