1. Departments of Safety Science and Pharmacokinetics, Dynamics and Metabolism, Pfizer Global Research and Development, Ann Arbor, Michigan 48105, Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania 15261, and Department of Medicinal Chemistry, School of Pharmacy, University of Washington, H364C Health Sciences Center, P.O. Box 357631, Seattle, Washington 98195-763.