Induction of VAMP2 mRNA after chronic antidepressant treatment (a) and repeated ECT (b) revealed by RT-PCR. Total RNA was extracted from rat frontal cortex treated either with vehicle (control, lanes a1–3), 10 mg/kg of imipramine (lanes a4–6) or 10 mg/kg of sertraline (lanes a7–9) for 21 days, and used for RT-PCR analysis. Total RNA samples extracted from rat frontal cortex treated either with sham operation (control, lanes a1-3) or repeated ECT (lanes a4-6) were also used for RT-PCR analysis. The reproducible single band corresponding to VAMP2 at the size of 784 bp existed on a gel. This figure represents a typical result of three independent experiments. Treatment with imipramine or sertraline increased the expression of VAMP2 in rat frontal cortex when compared to control samples (a). In addition, repeated ECT also increased the expression of VAMP2 in rat frontal cortex when compared to control samples (b).