Figure 4. Time-course of the release of3Hydrogen-GABA elicited by various depolarizing agents from preloaded striatal synaptosomes: baseline (open square), potassium chloride 9 mM (closed triangle), potassium chloride 15 mM (diamond), and potassium chloride (9 mM) in a Calcium2+-free medium (open triangle). Depolarizing stimuli were applied between minutes 8 and 13. Experiments were performed in the presence of nipecotic acid (10 sup -3 M). Data are mean plus/minus SD. *P < 0.05. **P < 0.01. ***P < 0.001.