Figure 3.

Effect of chronic treatment with fluoxetine on the release of glutamate and GABA from rat hippocampal synaptosomes. Fluoxetine was administered by means of osmotic minipumps (10 mg/kg daily). After 14 d of treatment, animals were killed for release experiments. Synaptosomes were exposed in superfusion to KCl (15 or 25 mm) or ionomycin (0.5 or 1 μm), and the stimulus-evoked overflow of endogenous glutamate (A) and GABA (B) was monitored. The stimulus-evoked overflow was calculated by subtracting the neurotransmitter content in the basal outflow from the release evoked by stimulation (see the legend to Fig. 1). Data represent the means ± SEM of four to five separate experiments run in triplicate. ^*p < 0.05 versus the respective control value (two-tailed Student's t test). Open bars, Vehicle-treated animals; filled bars, fluoxetine-treated animals.