title: Locally application of amphetamine into the ventral tegmental area enhances dopamine release in the nucleus accumbens and the medial prefrontal cortex through noradrenergic neurotransmission.
abstract: The effects and mechanisms of locally applied d-amphetamine (AMPH) into the ventral tegmental area (VTA) on extracellular dopamine (DA) concentrations in both the nucleus accumbens (N ACC) and the medial prefrontal cortex (mPFC) were investigated. A solution containing either, 0, 100, 500 or 1000 microM AMPH was infused, using a 1-ml Hamilton syringe, into the VTA of chloral hydrate-anesthetized rats for 100 min through a microdialysis probe. Infusion of AMPH into the VTA dose-dependently increased extracellular DA in the N ACC and in the mPFC. The introductory rate of AMPH application through the dialysis probe into the VTA was estimated simultaneously. Local infusion of either a selective alpha adrenoceptor antagonist (phentolamine, 1 and 10 microM) or a selective beta adrenoceptor antagonist (alprenolol, 1 and 10 nM) dose-dependently blunted the intra-VTA AMPH-induced extracellular DA increase in the N ACC. Further, local infusion of phentolamine (0.1 and 1 microM) and alprenolol (1 and 10 nM) appreciably and dose-dependently reduced the effects of AMPH on the DA increase in the mPFC. These results suggest that intra-VTA AMPH can enhance DA release in the N ACC and in the mPFC by activating noradrenergic neurotransmission in the VTA.
authors.affiliation: Institute of Pharmacology, School of Life Sciences National Yang-Ming University, Taipei, Taiwan, Republic of China.
authors.forename: W H
authors.initials: WH
authors.lastname: Pan
authors.forename: J C
authors.initials: JC
authors.lastname: Sung
authors.forename: S M
authors.initials: SM
authors.lastname: Fuh
mesh_terms: D000661:Amphetamine / Q000494:pharmacology*; D000818:Animals; D004298:Dopamine / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D008297:Male; D018377:Neurotransmitter Agents / Q000378:metabolism*; D009714:Nucleus Accumbens / Q000187:drug effects* / Q000378:metabolism; D017397:Prefrontal Cortex / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D018377:Neurotransmitter Agents; D000661:Amphetamine; D004298:Dopamine