1. Institute of Pharmacy, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany; Department of Psychiatry, University of Bonn, Sigmund-Freud-Str. 25, D-53105 Bonn, Germany; and Institute of Pharmacy, Friedrich-Schiller-University Jena, Philosophenweg 14, D-07743 Jena, Germany