1. Departments of Physiology and Pharmacology (M.P., G.F.W.), Faculty of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada N6A 5C1
2. Departments of Biochemistry (G.E.D.), and Obstetrics and Gynecology (G.E.D.) and Faculty of Medicine and Dentistry, University of Western Ontario, and London Regional Cancer Center (G.E.D.), London, Ontario, Canada N6A 5C1