1. Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innrain 52a, A-6020 Innsbruck, Austria
2. Department of Physiology and Pharmacology, Karolinska Institutet, S-171 77 Stockholm, Sweden
3. Biosciences Division, SRI International, 333 Ravenswood Avenue, Menlo Park, California 94025, United States
4. Department of Pharmacology and Pharmacotherapy, Medical Faculty, Semmelweis University, Nagyvarad ter 4, POB 370, H-1445 Budapest, Hungary