Convergent evidence suggests that amphetamine (AMPH) exerts its rewarding and locomotor stimulating effects via release of dopamine in the nucleus accumbens. However, there is no consensus as to the relative contributions of core and medial shell subregions to these effects. Moreover, the literature is based primarily on intracranial administration, which cannot fully mimic the drug distributio...

Introduction: This study was performed to evaluate the effects of intra-nucleus accumbens shell microinjection of Larginine (NO precursor) and L-NAME (nitric oxide synthase (NOS) inhibitor) on morphine withdrawal signs in male rats. Method: Rats were anaesthetized with a combination of ketamine and xylazine, and placed in stereotaxic apparatus, and a guide cannula was inserted into nucleus accu...

Effects of direct injections of amphetamine into the shell of the nucleus accumbens were studied in three lines of Long-Evans rats, two of which had been selected for low and high rates of 50 kHz calls in adolescence in response to a standard social stimulation, and compared to results from randomly selected rats. Injections of amphetamine into the medial shell of the nucleus accumbens signific...

One of the primary outputs of the nucleus accumbens is directed to the mediodorsal thalamic nucleus (MD) via its projections to the ventral pallidum (VP), with the core and shell regions of the accumbens projecting to the lateral and medial aspects of the VP, respectively. In this study, the multisynaptic organization of nucleus accumbens projections was assessed using intracerebral injections ...

Microinjection of opioid agonists, such as morphine, into the nucleus accumbens shell produces increases in eating behavior (i.e. 'wanting' for food). This study (1) reports direct evidence that activation of accumbens opioid receptors in rats also augments food 'liking', or the hedonic impact of taste, and (2) identified a neural site that definitely contains receptors capable of increasing fo...

We used an ABA renewal design to study the neural correlates, and role of D1 dopamine receptors, in contextual control over extinguished alcohol-seeking. Rats were trained to respond for 4% beer in one context (A), extinguished in a different (B) context, and then tested for responding in the original training context (A) or the extinction context (B). ABA renewal was mediated by D1 dopamine re...

There are multiple neurotransmitters and neuromodulator systems mediating memory formation among which the endocannabinoid system plays a critical role in the memory formation by modulating the release of many neurotransmitters. Nucleus accumbens appears to have a site in the central of neuronal circuits of the limbic system and to be responsible for the integration and consolidation of inputs ...

The dopaminergic innervation of the nucleus accumbens is generally agreed to mediate the primary reinforcing and locomotor effects of psychostimulants, but there is less consensus on conditioned dopamine (DA) release during drug-seeking behavior. We investigated the neurochemical correlates of drug-seeking behavior under the control of a drug-associated cue [a light conditioned stimulus (CS+)] ...

Colocalization of proenkephalin and prodynorphin mRNAs with each other as well as with D1, D2, and D3 dopamine receptor mRNAs was analyzed in the nucleus accumbens of the rat. Distinct combinations were detected in the rostral pole, core, and shell subdivisions of the nucleus accumbens. Proenkephalin and prodynorphin mRNAs were principally localized in separate cells in the core. All detectable...

glutamatergic system stimulationthe nucleus accumbens shell, may affect anxiety-related behaviors, aversive learning and memory. glutamate receptors are differentially distributed in pre- and postsynaptic sites contributing to neuronal communications.the present study aimed to examine the possible involvement of the nac shell presynaptic nmda receptors on nmda induced responses, using the eleva...