1. Institute of Physiology, Academy of Sciences of Czech Republic, Vídeòská 1083, 142 20 Prague, Czech Republic
2. Neurologic Clinic, 1st Medical Faculty of Charles University, Kateøinská 30, 120 00 Prague, Czech Republic
3. Neurosciences Group, Department of Clinical Neurology, Institute of Molecular Medicine, John Radcliffe Hospital, Oxford OX3 9DU, United Kingdom