Previous findings from this laboratory demonstrate: (1) that different classes of addictive drugs require intact norepinephrine (NE) transmission in the medial pre Frontal Cortex (mpFC) to promote conditioned place preference and to increase dopamine (DA) tone in the nucleus accumbens shell (NAc Shell); (2) that only food-restricted mice require intact NE transmission in the mpFC to develop con...

The transcription factor cAMP response element (CRE)-binding protein (CREB) has been shown to regulate neural plasticity. Drugs of abuse activate CREB in the nucleus accumbens, an important part of the brain's reward pathways, and local manipulations of CREB activity have been shown to affect cocaine reward, suggesting an active role of CREB in adaptive processes that follow exposure to drugs o...

Administration of opioid drugs such as heroin produces several immunosuppressive effects, including decreases in natural killer (NK) cell activity, lymphocyte proliferative responses, and nitric oxide production. Interestingly, opioids have been shown to alter many immune parameters indirectly by modulating the immunoregulatory actions of the central nervous system. Recently, it has been demons...

The nucleus accumbens (NAc) has been implicated in a variety of associative processes that are dependent on the integrity of the amygdala and hippocampus (HPC). However, the extent to which the two subregions of the NAc, the core and shell, form differentiated circuits within the amygdala- and hippocampal-ventral striatal circuitry remains unclear. The present study investigated the effects of ...

OBJECTIVE(S) The dopamine level of the nucleus accumbens changes during some stereotyped behaviors. To study dopamine level of the nucleus accumbens in intra infralimbic apomorphine-induced climbing, microdialysis probes were implanted into the nucleus accumbens shell of male Sprague Dawley rats weighting 275-400 g. MATERIALS AND METHODS The rats were divided into two groups (apomorphine and ...

Disgust is a prototypical type of negative affect. In animal models of excessive disgust, only a few brain sites are known in which localized dysfunction (lesions or neural inactivations) can induce intense 'disgust reactions' (e.g. gapes) to a normally pleasant sensation such as sweetness. Here, we aimed to map forebrain candidates more precisely, to identify where either local neuronal damage...

Contexts play an important role in controlling the expression of extinguished behaviors. We used an ABA renewal design to study the neural correlates, and role of D1 dopamine receptors, in contextual control over extinguished instrumental responding. Rats were trained to respond for a sucrose reward in one context (A). Responding was then extinguished in the same (A) or different (B) context. R...

Glutamate signals in the nucleus accumbens shell play an important role in generating appetitive and fearful motivation. Previous studies have indicated that AMPA/kainate blockade generates motivation along a rostrocaudal gradient that shifts from appetitive motivation in rostral shell to fearful motivation in caudal shell. This study compared the effects of AMPA/kainate blockade and NMDA stimu...

objective: the nucleus accumbens (nac) receive histaminergic neurons from tuberomammillary nuclei. there are reports indicating that central histamine systems are involved in many physiological behavioral processes, including anxiety. the aim of the present study was to assess whether the histaminergic system of the nac is involved in anxiety-related behaviors. methods:   rats   were   anesthet...

The core and shell subregions of the nucleus accumbens receive differential projections from areas of the medial prefrontal cortex that have dissociable effects on impulsive and perseverative responding. The contributions of these subregions to simple instrumental behaviour, inhibitory control and behavioural flexibility were investigated using a 'forced choice' task, various parameter manipula...