Opposite effects of prefrontal cortex and nucleus accumbens infusions of flupenthixol on stimulant-induced locomotion and brain stimulation reward.
Ventral tegmental area (VTA) stimulation produced conditioned place preferences for stimulation-paired environments the magnitudes of which were dose-dependently reduced by systemic application of the dopamine antagonist, haloperidol (0.0, 0.15, 0.3 mg/kg). Bilateral microinjections of cis-flupenthixol (FLU) into the nucleus accumbens (0.0, 1.0, 5.0 or 10.0 micrograms) also resulted in reductions in the size of stimulation-induced place preferences as well as reductions in the magnitude of the hyperlocomotor response to 1.5 mg/kg (s.c.) D-amphetamine. Comparable microinjections of FLU into the medial prefrontal cortex (PFC) produced diametrically opposite effects: the size of VTA stimulation-induced place preferences was either unaffected (1.0 and 5.0 microgram groups) or slightly increased (10 micrograms group) and amphetamine-stimulated hyperlocomotion was dose-dependently potentiated. These behavioral findings suggest a dopamine-mediated modulatory role for the PFC over reward relevant elements within the nucleus accumbens.
Duvauchelle
C L
CL
Department of Psychology, University of California, Santa Barbara 93106.
Levitin
M
M
MacConell
L A
LA
Lee
L K
LK
Ettenberg
A
A
D000818:Animals; D003216:Conditioning, Operant / Q000187:drug effects*; D003913:Dextroamphetamine / Q000037:antagonists & inhibitors / Q000494:pharmacology; D004558:Electric Stimulation; D005475:Flupenthixol / Q000008:administration & dosage / Q000494:pharmacology*; D005625:Frontal Lobe / Q000187:drug effects / Q000502:physiology*; D006220:Haloperidol / Q000494:pharmacology*; D007263:Infusions, Parenteral; D008297:Male; D008845:Microinjections; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology*; D009714:Nucleus Accumbens / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D012201:Reward; D013239:Stereotyped Behavior / Q000187:drug effects; D013681:Tegmentum Mesencephali / Q000502:physiology*
D005475:Flupenthixol; D006220:Haloperidol; D003913:Dextroamphetamine