RT Journal Article
SR Electronic
T1 Role of Dopamine D<sub>1</sub> and D<sub>2</sub> Receptors in the Nucleus Accumbens in Mediating Reward
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 8580
OP 8587
DO 10.1523/JNEUROSCI.17-21-08580.1997
VO 17
IS 21
A1 Satoshi Ikemoto
A1 Bradley S. Glazier
A1 James M. Murphy
A1 William J. McBride
YR 1997
UL http://www.jneurosci.org/content/17/21/8580.abstract
AB The objectives of this study were to examine the involvement of D1 and D2 receptors within the nucleus accumbens (ACB) in mediating reinforcement. The intracranial self-administration (ICSA) of D1 and D2agonists was used to determine whether activating D1 and/or D2 receptors within the ACB of Wistar rats is reinforcing. At concentrations of 0.25, 0.50, and 1.0 mm (25, 50, and 100 pmol/100 nl of infusion), neither the D1 agonistR(+)-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine-7,8-diol [SKF 38393 (SKF)] hydrochloride nor the D2 agonist (−)-quinpirole (Quin) hydrochloride was self-administered into the shell region of the ACB. On the other hand, equimolar mixtures of SKF and Quin (SKF+Quin), at concentrations of 0.25, 0.50, and 1.0 mm each, were significantly self-infused into the ACB shell. The core region of the ACB did not support the ICSA of SKF+Quin at any of these concentrations. Rats increased lever pressing when the response requirement was increased from a fixed ratio 1 (FR1) to FR3, and they responded significantly more on the infusion lever than they did on the control lever. Coadministration of either 0.50 mmR(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine (SCH 23390) hydrochloride, a D1 antagonist, or 0.50 mmS(−)-sulpiride, a D2antagonist, completely abolished the ICSA of the mixture of SKF+Quin (each at 0.50 mm) into the ACB shell. The present results suggest that concurrent activation of D1- and D2-type receptors in the shell of the ACB had a cooperative effect on DA-mediated reward processes.