R(-8-OH-DPAT, A 5-HT1A RECEPTOR AGONIST, INHIBITS AMPHETAMINE-INDUCEDSEROTONIN AND DOPAMINE RELEASE IN RAT MEDIAL PREFRONTAL CORTEX())

Pretreatment with R(+)-8-OH-DPAT, a selective serotonin (5-HT)(1A) rec eptor agonist (50 mu g/kg, s.c.), inhibited D-amphetamine sulfate (1.0 mg/kg, s.c.)-induced increases in extracellular levels of both 5-HT a nd dopamine (DA) in rat medial prefrontal cortex, as determined by in vivo microdialysis. The inhibitory effect of R(+)-8-OH-DPAT was comple tely reversed by the selective 5-HT1A, receptor antagonist WAY 100,635 (100 mu g/kg s.c.) administered 5 min prior to R(+)-8-OH-DPAT. These results suggest that stimulation of 5-HT(1)A receptors may inhibit amp hetamine-induced release of 5-HT and DA in the medial prefrontal corte x.