BASAL EXTRACELLULAR DOPAMINE IN THE NUCLEUS-ACCUMBENS DURING AMPHETAMINE WITHDRAWAL - A NO NET FLUX MICRODIALYSIS STUDY

The basal extracellular concentration of dopamine in the nucleus accum bens was quantified using the 'no net flux' microdialysis method, in r ats undergoing withdrawal from D-amphetamine. Rats were initially pret reated with saline, or an escalating dose amphetamine regimen known to produce a robust withdrawal syndrome, and extracellular dopamine was quantified 3 or 28 days after the last pretreatment injection. There w as no effect of amphetamine pretreatment on the basal extracellular co ncentration of dopamine in the nucleus accumbens, or on the 'in vivo r ecovery' of dopamine, estimated by 'no net flux' microdialysis. It is suggested that amphetamine withdrawal is not necessarily accompanied b y changes in the basal extracellular concentration of dopamine in the nucleus accumbens.