2.3.1. Rat synaptosome preparation
Rat synaptosome suspensions were prepared as described, with minor modifications (Pubill et al., 2005). Briefly, in each experiment two rats were decapitated under isofluorane anesthesia and the striatum was dissected out, homogenized (x20 volumes; 5 mM Tris-HCl and 320 mM sucrose in Milli-Q water) and centrifuged at 1,000xg, 4°C for 10 min. After discarding the pellet, the supernatant was centrifuged at 13.000 x g for 30 minutes at 4 °C. Then the supernatant was discarded and the pellet was diluted in HEPES-buffered solution (composition in mM: 140 NaCl, 5.37 KCl, 1.26 CaCl2, 0.44 KH2PO4, 0.49 MgCl2.6H2O, 0.41 MgSO4.7H2O, 4.17 NaHCO3, 0.34 Na2HPO4. 7H2O, 5.5 glucose and 20 HEPES-Na) containing pargyline (20 mM) and ascorbic acid (1 mM).