RT Journal Article SR Electronic T1 Methamphetamine-Induced Rapid and Reversible Changes in Dopamine Transporter Function: An In Vitro Model JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP 1413 OP 1419 DO 10.1523/JNEUROSCI.21-04-01413.2001 VO 21 IS 4 A1 Verónica Sandoval A1 Evan L. Riddle A1 Yvette V. Ugarte A1 Glen R. Hanson A1 Annette E. Fleckenstein YR 2001 UL http://www.jneurosci.org/content/21/4/1413.abstract AB This laboratory has demonstrated that a single methamphetamine (METH) injection rapidly and reversibly decreases the activity of the dopamine transporter (DAT), as assessed ex vivo in synaptosomes prepared from treated rats. This decrease does not occur because of residual drug introduced by the original injection or nor is it associated with a change in binding of the DAT ligand WIN35428. The purpose of this study was to elucidate the mechanism or mechanisms of this METH effect by determining whether direct application of this stimulant to synaptosomes causes changes in DAT similar to those observed ex vivo. Similar to the ex vivoeffect, incubation of striatal synaptosomes with METH decreased DAT activity, but not WIN35428 binding: the effect on activity was not eliminated by repeated washing of synaptosomes. Also, as observedex vivo, incubation with 3,4-methylenedioxymethamphetamine, but not cocaine or methylphenidate, caused a METH-like reduction in DAT function. The rapid and reversible METH-induced diminution in DAT activity did not occur because of a change in membrane potential, as assessed in vitro andex vivo by [3H]tetraphenylphosphonium accumulation. However, the METH-related decline in DAT function may be attributed to phosphorylation because NPC15437, a protein kinase C inhibitor, attenuated the METH-induced decline in DAT function. Similarities between previously reported effects ex vivo of a single METH injection on serotonin and norepinephrine transporter function and effects of direct METH application in vitro were also found. Together, these data demonstrate that the in vitro incubation model mimics the rapid and reversible effects observed after a single METH injection.