PD-135158, a CCKB receptor antagonist, microinjected into the nucleus accumbens and the expression of conditioned rewarded behavior.
Cholecystokinin (CCK) has been localized in the nucleus accumbens (NAC) where it may interact with dopamine neurotransmission. NAC dopamine is involved in the control over behavior produced by conditioned rewards. The present experiment examines whether the blockade of CCKB receptors in the NAC with microinjection of PD-135158 (10 micrograms in 0.5 microliter) potentiates bar-pressing for stimuli previously associated with food reward. Intra-NAC microinjections of amphetamine (10 micrograms in 0.5 microliter) increased the number of bar presses for conditioned reward presentation. Furthermore, similar administration of PD-135158 produced no significant effect on responding when administered alone but potentiated the level of amphetamine responding. These findings suggest that endogenous CCKB mechanisms in the NAC may normally inhibit dopamine function in reward-related behaviors.
Josselyn
S A
SA
Department of Psychology, University of Toronto, Ontario, Canada.
Franco
V P
VP
Vaccarino
F J
FJ
D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology*; D001522:Behavior, Animal / Q000187:drug effects; D007211:Indoles / Q000494:pharmacology*; D008297:Male; D008536:Meglumine / Q000031:analogs & derivatives* / Q000494:pharmacology; D008845:Microinjections; D009714:Nucleus Accumbens / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D011949:Receptors, Cholecystokinin / Q000187:drug effects*; D012201:Reward
D014151:Anti-Anxiety Agents; D007211:Indoles; D011949:Receptors, Cholecystokinin; C065600:PD 135158; D008536:Meglumine