Event Abstract Back to Event Dopamine release in motivated behaviour Jorge Mendez1* 1 a, Albania Goal-directed behavior is powerfully shaped by rewarding and aversive stimuli. Changes in DA concentration in the nucleus accumbens (NAc), a region of the basal ganglia critical for goal-directed behavior, are correlated with reward-directed behavior. Recently, phasic (millisecond) changes in dopamine activity have received particular attention as they relate to reward-related learning and action selection. We have shown, using fast-scan cyclic voltammetry in awake and behaving rats, that spontaneous, phasic changes in DA concentration in the NAc time-average to what appears to be a steady-state level. We delivered both rewarding (sucrose) and aversive (quinine) taste stimuli directly into the oral cavity of the awake rat. Unconditioned reward evoked an increase in DA concentration from the time-averaged steady-state level while unconditioned aversion evoked a decrease. Individual trials revealed that this modulation was due to changes in the probability of observing phasic DA release. Kappa opioid receptors play a critical role in behavioral responses to stressful and aversive stimuli and are expressed on DA terminals and cell bodies. We characterized the effects of the kappa opioid receptor agonist salvinorin A (salvA) on phasic DA signaling. Administration of salvA (2mg/kg, i.p.) suppressed phasic DA release evoked by electrical stimulation to 37±2% of baseline. SalvA also shifted the frequency-response function for DA release to the right. The implications of these findings for goal-directed behavior were investigated using the progressive ratio paradigm. SalvA dose-dependently decreased operant responding on a progressive ratio. This deficit was compensable when a fixed ratio 5 paradigm was used and eliminated the possibility of motor impairment. Taken together, the data support the idea that phasic DA signaling is differentially modulated by rewarding and aversive stimuli and this modulation can have profound effects on motivated behavior. Conference: 41st European Brain and Behaviour Society Meeting, Rhodes Island, Greece, 13 Sep - 18 Sep, 2009. Presentation Type: Oral Presentation Topic: Symposia lectures Citation: Mendez J (2009). Dopamine release in motivated behaviour. Conference Abstract: 41st European Brain and Behaviour Society Meeting. doi: 10.3389/conf.neuro.08.2009.09.046 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 05 Jun 2009; Published Online: 05 Jun 2009. * Correspondence: Jorge Mendez, a, a, Albania, mroitman@uic.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Jorge Mendez Google Jorge Mendez Google Scholar Jorge Mendez PubMed Jorge Mendez Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.