FIG. 5.

Effects of VPA and PI3K inhibition on rat synaptosomal glutamate release. VPA (1, 3, and 10 mM), PI3K inhibitor (LY294002; 100 μM), and a GABA transaminase inhibitor (vigabatrin; 100 μM) were incubated with synaptosomes for 10 min before depolarization with 4-aminopyridine to evoke calcium-dependent glutamate release. Release traces shown are means ± standard errors (n = 3 to 5) from independent synaptosomal preparations. Only the error bar at 4 min after initiation of release is shown. Significant changes were determined by one-way analysis of variance followed by a post-hoc Fisher's least-significant-difference procedure to compare release in the presence of drug with control release. *, significant difference versus control release (P < 0.05). Each n indicates the number of experiments carried out using individual synaptosome preparations independently derived from five to seven animals.