1. Department of Pharmacology, University of Tartu (A.K., R.P., L.R.), Ulikooli 18, 50090 Tartu, Estonia;
2. the Department of Medicinal Chemistry (F.M., I.M.) Institute of Organic Synthesis, Aizkraukles 21, LV-1006, Riga, Latvia;
3. the Department of Pharmaceutical Pharmacology, Uppsala University (F.M., R.M., I.M., J.E.S.W., H.B.S.), 751 24 Uppsala, Sweden
4. the Laboratory of Pharmacology (R.M.), Institute of Organic Synthesis, Aizkraukles 21, LV-1006, Riga, Latvia;