Effect of a fast-acting reserpine-like drug, Ro4–1284 (10 μm), and AMPH (10 μm) on stimulated and baseline release of DA. Individual recordings of DA efflux measured by cyclic voltammetry in striatal slices from wild-type (DAT +/+) and homozygote DAT knockout mice (DAT −/−). Drugs were applied to slices at the times indicated by the large arrows. Top, Single-pulse stimulations were applied to a slice from a wild-type mouse at the times indicated by thesmall arrowheads. Inset, Cyclic voltammograms, current (nA) versus potential (mV) plots, recorded during postcalibration with authentic DA (solid line) and during the plateau phase of the release induced by AMPH (filled circles), are plotted for comparison.Bottom, Single-pulse stimulations were applied to a slice from a homozygote DAT knockout mouse at the times indicated by the small arrowheads.