Figure 2.

TCTP stimulates both basal spontaneous and depolarization (50 mM KCl)-induced release of dopamine from PC12 cells. PC12 cells preloaded with [³H]dopamine were washed and incubated at 37 °C with rat recombinant TCTP (RrTCTP) (15 µg/mL, (A,B); 5–40 µg/mL, (C)), GST-tagged mouse recombinant TCTP (GST-MrTCTP) (50 µg/mL, (A)) or GST (50 µg/mL, (A)) for 20 min (A,C) or indicated time periods (B), under basal (5 mM KCl) or high K⁺ (50 mM KCl) KR buffer conditions. The amount of [³H]dopamine released into the culture supernatant was significantly increased by both RrTCTP and GST-MrTCTP, but not by GST alone (A). The rTCTP-induced stimulation of dopamine release was time- (B) and dose-dependent (C). * p < 0.05 relative to basal control release; † p < 0.05 relative to high K⁺ control release; # p < 0.05 relative to basal release.