1. Dept. Pharmacology & Pharmacotherapy, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ Amsterdam, Netherlands, Tel.: +31 20 566 6762; Fax: +31 20 696 5976;
2. Dept. of Urology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ Amsterdam, Netherlands