[Abstract Title]. - Society for Neuroscience

hand injections of 3.0 κg of eticlopride (D2 receptor antagonist) modestly enhanced maximum
rates while injections of 10 κg of quinpirole (D2 receptor agonist) did the opposite. Eticlopride
also slightly decreased the frequency required to maintain half-maximal responding. Maximum
rate shifts were more pronounced than required frequency shifts, suggesting a stronger role for
SLEAc D2 receptors in governing responding for rewards than in evaluating the stimulation‟s
reward efficacy. The D2 drugs were effective only when they were injected contralateral to the
stimulation site, possibly because the MFB stimulation may have directly driven neural activity
in the ipsilateral SLEAc that overcame any effects of manipulating D2 receptors. The modest
nature of the D2 drugs‟ effects might indicate that dopaminergic input to the SLEAc is secondary
to, and perhaps interacts with, a more primary input such as glutamate in controlling reward
functions.
Disclosures: B. Farral, None; M.A. Waraczynski , None.
Poster
298. Neural Mechanisms of Reward: Self-Administration and Opioid Modulation
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 298.22/TT55
Topic: F.03.d. Reward
Support: CIHR
Title: OSU-6162, a dopamine stabilizer, acts at both pre- and post-synaptic receptor sites to alter
brain stimulation reward and locomotor activity
Authors: *F. BENALIOUAD 1,2 , P.-P. ROMPRÉ 2,3 , S. KAPUR 4 ;
1 Ctr. Fernand-Seguin, Montreal, QC, Canada; 2 Physiol., 3 Psychiatry, Univ. of Montreal,
Montreal, QC, Canada; 4 Psychiatry, King's Col. London - Univ. of London, London, United
Kingdom
Abstract: OSU-6162 belongs to a new class of drugs named dopamine stabilizers on the basis of
their ability to maintain a certain homeostasis of the dopamine function. This molecule displays
specificity for dopamine receptors and acts as a partial agonist at the type 2 (D2) receptor (Ki =
447 nM for D2 receptors and Ki > 1µM for other receptors). Previous studies showed that OSU-
6162 increases locomotor activity in rats habituated to the testing environment but reduces
amphetamine-induced locomotion. In a previous study, we showed that OSU-6162 produced a
dose-orderly attenuation of operant responding for brain stimulation reward, a dopamine
sensitive behaviour. This attenuation effect suggests that OSU-6162 acts at both pre-synaptic and
post-synaptic dopamine receptor sites. This study was aimed at testing this hypothesis.