RU-43044 inhibited METH-induced increases in extracellular dopamine (DA), but not serotonin (5-HT), levels in the prefrontal cortex, but did not affect METH-induced increases in extracellular DA levels in the nucleus accumbens shell, although it inhibited increases in extracellular 5-HT levels.
Cocaine was intravenously infused into anesthetized rats, according to inter-infusion intervals obtained from self-administering animals, and dopamine uptake changes (apparent K(m)) were assessed in the nucleus accumbens using voltammetry.
There was significantly lower expression for C allele (rs910079), with ratios ranging from 0.48 to 0.78, indicating lower expression of the CCT haplotype of PDYN in both the caudate and nucleus accumbens.
Current brain imaging studies indicate that dysfunction of dopaminergic, glutamatergic and opioidergic neurotransmission in the brain reward system (ventral striatum including the nucleus accumbens) can be associated with alcohol craving and functional brain activation in neuronal systems that process attentional relevant stimuli, reward expectancy and experience.
Five general brain regions contained retrogradely labeled neurons: cerebral cortex (infralimbic and insular regions), rostral forebrain structures (subfornical organ, organum vasculosum of the lamina terminalis, taenia tecta, nucleus accumbens, lateral septum, endopiriform nucleus, dorsal BST, substantia innominata, and, most prominently the amygdala-primarily its basomedial and central subnuclei), thalamus (central medial, intermediodorsal, reuniens, and, most prominently the paraventricular thalamic nucleus), hypothalamus (medial preoptic area, perifornical, arcuate, dorsomedial, parasubthalamic, and posterior hypothalamic nuclei), and brainstem (periaqueductal gray matter, dorsal and central superior raphe nuclei, parabrachial nucleus, pre-locus coeruleus region, NTS, and A1 noradrenergic neurons in the caudal ventrolateral medulla).
In nucleus accumbens (NAcc), signal change increased with anticipated reward magnitude (with intermediate recruitment by variable incentives) but not with loss magnitudes.
The binding of [ (3)H]CGP 54626 in the nucleus accumbens subareas and the amygdala was decreased by ca. Similar decreases in the nucleus accumbens were seen in the animals passively receiving cocaine.
In contrast, the same two doses of risperidone decreased NMDA receptors in nucleus accumbens of juveniles and not adults.
The transcription factor deltaFosB (DeltaFosB), induced in nucleus accumbens (NAc) by chronic exposure to drugs of abuse, has been shown to mediate sensitized responses to these drugs.
The neuroanatomical site(s) of key neuroadaptations may include nucleus accumbens (NAc) where changes in D-1 dopamine (DA) receptor-mediated cell signaling and gene expression have been documented.
Objective: To investigate the short-term psychological function of opiate addicts who have undergone ablative stereotactic surgery targeting the nucleus accumbens (NAc) for alleviating opiate drug psychological dependence.
Abstract: Objective To observe the effects of gamma-aminobutyric acid (GABA) on the electric activities of pain-excited neurons (PEN) in nucleus accumbens (NAc) in central nervous system (CNS) of morphine-dependent rats.
No change in D2 receptor mRNA expression was found in the dorsal striatum, nucleus accumbens and substantia nigra.
The metabolic activity of the nucleus accumbens, the subthalamic nucleus, the corpus amygdaloideum and the red nucleus was normal.
METHODS: Functional magnetic resonance imaging (fMRI) hemodynamic responses to novelty and reward (monetary incentive) from the substantia nigra/ventral tegmental area (SN/VTA), the nucleus accumbens (NAcc), and the hippocampus of 29 subjects were correlated with novelty-seeking scores.
The involvement of dopamine (DA) mechanisms in the nucleus accumbens (NAC) in fear conditioning has been proposed by many studies that have challenged the view that the NAC is solely involved in the modulation of appetitive processes.
Several regions of interest, including the bilateral nucleus accumbens, caudate nucleus, anterior insula, right cerebellar lobule VI, and left putamen, were sensitive to informative feedback regardless of valence.
RESULTS: This study examined the effect of chronic administration of pseudoephedrine in rat nucleus accumbens and striatum and identified three further similarities to amphetamine.
Further, increases in 5-HT levels in dorsal hippocampus, basolateral amygdala, nucleus accumbens, and striatum were likewise potentiated, and GR205171 similarly facilitated the influence of fluoxetine upon levels of 5-HT, as well as dopamine and noradrenaline.
A recent lesion study suggests that expression of ethanol-conditioned behaviors depends upon an intact amygdala and nucleus accumbens core.
Specifically, an activation likelihood estimate meta-analysis of cued response studies indicates that nucleus accumbens (NAcc) activation increases during gain anticipation relative to loss anticipation, while anterior insula activation increases during both loss and gain anticipation.
Thus, regions of the brain's reward circuitry, such as the nucleus accumbens, are promising alternatives for DBS in obesity control.
In this study, we show that a single cocaine administration (30 mg/kg) time-dependently increases ERK phosphorylation, c-Fos and FosB protein expression, and MKP-1 phosphorylation (p-MKP-1), in the caudate-putamen (CPu) and nucleus accumbens (NAc) of Fischer rats.
Testosterone was administered intranasally in anesthetized male rats, and its effects on the activity of dopaminergic and serotonergic neurons in the neostriatum and nucleus accumbens were assessed by means of microdialysis and HPLC. In the nucleus accumbens, dopamine and serotonin increased after 1.0 mg/kg and 2.0 mg/kg doses.
Novel surface-based anatomical modelling methods were applied to magnetic resonance imaging data to examine regional changes in the shape and volume of the caudate, the putamen and the nucleus accumbens in 21 patients (19 males/2 females; mean age=30.7+/-7.3) who were either antipsychotic-naïve or antipsychotic-free for at least 1 year and 21 healthy comparison subjects (19 males/2 females; mean age=31.1+/-8.2). Left and right global putamen volumes were significantly smaller in patients than controls; no significant global volume effects were observed for the caudate and the nucleus accumbens.
Results identified two separable pathways that together explained approximately 50% of the reported variance in self-reported emotion: (1) a path through nucleus accumbens that predicted greater reappraisal success, and (2) a path through ventral amygdala that predicted reduced reappraisal success (i.e., more negative emotion).
use a novel mediation analysis of neuroimaging data to show two independent pathways for the control of emotion by the prefrontal cortex: a path through the amygdala predicts a greater negative emotional response, and a path through the nucleus accumbens/ventral striatum predicts a greater positive response..
The nucleus accumbens (NAc) is an integral part of limbic circuits proposed to play a central role in the pathophysiology of schizophrenia, and is positioned to integrate information from limbic and cortical regions, including the medial prefrontal cortex (mPFC) and the hippocampus.
Of the structures that receive direct projections from the cortex, the thalamus, caudate nucleus, nucleus accumbens, and hippocampus showed changes specific to subjects with schizophrenia, and changes in the amygdala and putamen were similar in both groups.
Using in situ hybridization, we examined the mRNA expression of 5-hydroxytryptamine transporter (5-HTT) and 5-hydroxytryptamine 1A receptor (5-HT1AR) in 3 crucial regions in addiction, namely the ventral tegmental area (VTA), the nucleus accumbens (NAc), and the medial prefrontal cortex (mPFC), during the dependence and withdrawal.
Short 50-kilohertz (kHz) range frequency-modulated ultrasonic vocalizations (USVs) produced by rats and mice are unconditionally elicited by drugs of abuse or electrical stimulation that increase dopamine activity in the nucleus accumbens, and it has been suggested that they reflect "positive affect" or incentive motivational states associated with appetitive behavior.
Expression of the dopamine D1-receptor transcript was elevated in the amygdala and decreased in the hippocampus while the transcript level of the dopamine D4-receptor was increased in the nucleus accumbens.
Prodynorphin mRNA increased by 30 min for over 24 h, and in situ hybridization demonstrated elevated signal in caudate/putamen and nucleus accumbens.
In mice injected with melanoma cells, the specific binding of [ (125)I]EYWSLAAPQRF-NH(2), an agonist of neuropeptide FF(2) receptors, was increased in several brain areas involved in the rewarding properties of opiates, including the shell of the nucleus accumbens, the major islands of Calleja, the ventral endopiriform nucleus and the amygdaloid area.
Its role in important brain structures such as the midbrain, the lateral septal complex, the hypothalamus, the olfactory bulb, the pons, the choroid plexus, the nucleus pallidus, the striatum and the amygdala, the nucleus accumbens and the anterior cingulated gyrus candidate it as a promising target for genetic association studies.
Expression of GAD67 mRNA was increased in many forebrain regions including all hippocampal cell layers, peri-paraventricular nucleus, bed nucleus stria terminalis, nucleus accumbens core and motor cortex, suggesting that long-term voluntary exercise enhances forebrain GABA synthesis capacity but in a region-specific manner.
Somatostatin levels were increased after citalopram, but not DMI administration, in the caudate-putamen, hippocampus, nucleus accumbens, and prefrontal cortex.
We examined the pattern of temperature fluctuations in the nucleus accumbens (NAcc), temporal muscle, and skin, along with locomotion in food-deprived and non-deprived rats following the presentation of an open or closed food container and during subsequent eating or food-seeking behavior without eating.
Binding studies show upregulation of high-affinity nAChRs after 21 days of treatment in cortical areas, caudate putamen, nucleus accumbens, hippocampus, ventral tegmental area, and superior colliculi.
The action of S33084 was regionally specific inasmuch as its injection into the nucleus accumbens or striatum was ineffective. A similar increase of recognition was obtained upon injection of the D(1) agonist, SKF81297 (0.04-0.63), into the FCX though it was also active (0.63) in the nucleus accumbens.
Here we challenge the view that reward-guided learning is solely controlled by the mesoaccumbens pathway arising from dopaminergic neurons in the ventral tegmental area and projecting to the nucleus accumbens. Whereas the nucleus accumbens is necessary for the acquisition and expression of certain appetitive Pavlovian responses and contributes to the motivational control of instrumental performance, the dorsal striatum is necessary for the acquisition and expression of instrumental actions.
We used rotating disk electrode voltammetry to examine dopamine clearance and inhibition of clearance by cocaine in the rat medial prefrontal cortex (mPFC) and nucleus accumbens (NAc).
RATIONALE: This study examined the relationship between voluntary ethanol consumption and ethanol concentrations measured in the nucleus accumbens of ethanol dependent and nondependent C57BL/6J mice.
The mechanism mediating the role of Drd3 in the control of responding by conditioned incentive stimuli remains unknown but it has been found that Drd3 receptors increase in number in the nucleus accumbens during conditioning.
Autoradiographic studies explored the effect of l-NNA on the expression of D(1) and D(2) receptors in the caudate-putamen (CPu) and nucleus accumbens (NAcc) at PD60.
Since acetylcholine (ACh) in the nucleus accumbens (NAc) normally increases as a meal progresses and satiety ensues, we also tested whether ACh release is altered when an animal has lost weight.
Overall, repeated ethanol administration desensitized IEG expression in both adolescent and adult mice, but this effect was greatest in the nucleus accumbens and prefrontal cortex of adolescents treated in the context-dependent paradigm.
The results showed that most of the forebrain structures known to receive neuronal projections from the VTA, including prefrontal cortex, nucleus accumbens, globus pallidus and caudate putaman, were enhanced at 24 h after injection of MnCl(2) into the ipsilateral VTA, and anesthesia seemed have little effects on the amount of Mn(2+)being transported from the VTA to these structures..
The nucleus accumbens regulates goal-directed behaviors by integrating information from limbic structures and the prefrontal cortex. Here, we review recent studies in an attempt to provide an integrated view of the control of information processing in the nucleus accumbens in terms of the regulation of goal-directed behaviors and how disruption of these functions might underlie the pathological states in drug addiction and other psychiatric disorders. We propose a model that could account for the results of several studies investigating limbic-system interactions in the nucleus accumbens and their modulation by dopamine and provide testable hypotheses for how these might relate to the pathophysiology of major psychiatric disorders..
The central extended amygdala (EAc) is an ensemble of highly interconnected limbic structures of the anterior brain, and forms a cellular continuum including the bed nucleus of the stria terminalis (BNST), the central nucleus of the amygdala (CeA) and the nucleus accumbens shell (AcbSh).
In nicotine-pretreated mice, morphine-induced dopamine release in the caudate putamen (CPu) and nucleus accumbens (NAc) was significantly augmented, as measured by microdialysis.
Synaptic relays from Nrg1(tm1Lwr) heterozygote ventral hippocampal slices to wild-type (WT) nucleus accumbens neurons (1) lack a sustained, alpha7*nAChRs-mediated phase of synaptic potentiation seen in comparable WT/WT circuits and (2) are deficient in targeting alpha7*nAChRs to presynaptic sites. Thus, selective alteration of the level of presynaptic type III Nrg1 dramatically affects the modulation of glutamatergic transmission at ventral hippocampal to nucleus accumbens synapses..
By contrast, activity in nucleus accumbens (NAcc) exhibits a differential response profile compared to OFC and subcallosal cingulate gyrus, suggesting a dissociable role between these regions in the reward processing of expertise.
Systemic and intracranial administration of HU210, a cannabinoid CB1R agonist, into the nucleus accumbens core (NAC) and prelimbic cortex (PrC) reinstated MAP-seeking behavior.
The expression of caspase 3 in prefrontal lobe cortex(PFC), hippocampus(HP) and nucleus accumbens(Acb) was detected by RT-PCR and Western blot on mouse postnatal day(P)14.
In the present study, we assessed the role of CB1 receptors within the key regions of the mesolimbic dopamine pathway, the nucleus accumbens (NAcc) and ventral tegmental area (VTA), in regulation of ethanol self-administration.
Cholinergic interneurons are the only known source of acetylcholine in the rat nucleus accumbens (nAcb); yet there is little anatomical data about their mode of innervation and the origin of their excitatory drive.
The results indicated that CB1 receptors within the nucleus accumbens are involved in the acquisition and expression of morphine-induced CPP in sensitized rats.
Other brain areas that also selectively demonstrated nicotine-related declines in SPLI content included prefrontal cortex, the nucleus accumbens shell, and the very posterior caudate.
Previous work from this laboratory has shown that intra-nucleus accumbens core infusions of a MEK inhibitor can interfere with reconsolidation of these drug-cue memories.
Available evidence tends to indicate that during W and REMS an increase of burst firing activity of DA neurons occurs together with an enhanced release of DA in the VTA, the nucleus accumbens and several forebrain structures.
In the present study we examined the efficacy of two muscarinic receptor agonists xanomeline and sabcomeline to increase the efflux of acetylcholine and dopamine in rat medial prefrontal cortex and nucleus accumbens. Microdialysis in awake, freely moving rats was used to demonstrate that xanomeline at 10, but not 1 or 3 mg/kg (s.c.), significantly increased acetylcholine efflux in both the medial prefrontal cortex and nucleus accumbens. Sabcomeline, at 1 but not 0.1 or 0.5 mg/kg (s.c.), significantly increased acetylcholine efflux in the medial prefrontal cortex but not the nucleus accumbens. Both xanomeline and sabcomeline dose-dependently increased dopamine efflux in the medial prefrontal cortex but only high dose of xanomeline (10 mg/kg, s.c.) and sabcomeline (1 mg/kg, s.c.) increased that in the nucleus accumbens.
Goal-directed actions are sensitive to work-related response costs, and dopamine in nucleus accumbens is thought to modulate the exertion of effort in motivated behavior. Dopamine-rich striatal areas such as nucleus accumbens also contain high numbers of adenosine A(2A) receptors, and, for that reason, the behavioral and neurochemical effects of the adenosine A(2A) receptor agonist CGS 21680 [ 2-p-(2-carboxyethyl) phenethylamino-5'-N-ethylcarboxamidoadenosine] were investigated.
Furthermore, we show that accurate prediction of DA content in VTA neurons is possible when the projection target is known: in both nucleus accumbens- and AMYG-projecting neural populations, AP durations are significantly longer in DA than non-DA neurons.
RATIONALE: Somatostatin and its receptors have been localized in brain nuclei implicated in motor control, such as the striatum, nucleus accumbens, ventral pallidum, and globus pallidus (GP).
RATIONALE: Food restriction (FR) enhances learned and unlearned behavioral responses to drugs of abuse and increases D-1 dopamine (DA) receptor-mediated activation of extracellular signal-regulated kinases (ERK) 1/2 MAP kinase in nucleus accumbens (NAc).
In this study we report that repeated forced swim stress caused a significant phosphorylation of extracellular signal-regulated kinase (ERK)1/2 a mitogen-activated protein kinase (MAPK) in both the caudate and nucleus accumbens regions of the mouse striatum.
The severity of disinhibition correlated with atrophy in the right nucleus accumbens, right superior temporal sulcus, and right mediotemporal limbic structures.
In the first, changes in dopamine tone in the nucleus accumbens were measured by means of microdialysis during prolonged subcutaneous infusions of cocaine.
GSK207040 (3.2 mg/kg) raised extracellular concentrations of dopamine, noradrenaline, and acetylcholine in the anterior cingulate cortex and c-fos expression in the core of the nucleus accumbens was increased at doses of 3.2 and 10.0 mg/kg.
The nucleus accumbens is gaining interest as a target for deep brain stimulation in refractory neuropsychiatric disorders with impulsivity as core symptom. The nucleus accumbens is composed of two subterritories, core and shell, which have different anatomical connections. Here, we tested the hypothesis that stimulation of the nucleus accumbens core and shell would have different effects on impulsivity. Rats received bilateral stimulation at the level of the nucleus accumbens core or shell during a reaction time task. Stimulation of the nucleus accumbens core significantly decreased impulsivity, while stimulation of the shell increased it. Our results support the hypothesis that the nucleus accumbens is a potential target to treat neuropsychiatric disorders related to impulsivity by deep brain stimulation.
Intra-nucleus accumbens (Acb) infusion of cholinergic muscarinic antagonist, scopolamine (10mug/0.5mul), markedly reduced fat intake elicited by intra-Acb treatment of the mu-opioid receptor agonist, DAMGO, with 30min and 4h pretreatment intervals.
Both the nucleus accumbens (NAc) and basolateral amygdala (BLA) contribute to learned behavioral choice.
Repeated exposure to cocaine causes sensitized behavioral responses and increased dendritic spines on medium spiny neurons of the nucleus accumbens (NAc).
nucleus accumbens dopamine is implicated in the primary and conditioned reinforcing properties of abused drugs. In the present study, specific impairments in responding for intravenous cocaine (0.3 mg/inf/0.1 ml/5 s) under a fixed-ratio 1 (FR-1) or second-order schedule (FI 15 min (FR10:S)) were investigated following infusion of the dopamine antagonist, alpha-flupenthixol, into either the nucleus accumbens core or shell. By comparison, blockade of nucleus accumbens shell dopamine receptors increased cocaine intake under the FR-1 schedule. These results are discussed with reference to a role for nucleus accumbens shell dopamine in instrumental responding, and a role of nucleus accumbens core dopamine in incentive motivation, perhaps under the control of contextual stimuli..
The dopamine level in the mouse nucleus accumbens was significantly increased by s.c.
The positive reinforcing/rewarding effects of drugs primarily depend on the mesocorticolimbic dopamine system innervating the nucleus accumbens while the craving for drugs is associated with activation of the prefrontal cortex.
Intraperitoneal administration induced Fos-IR in some additional regions including the nucleus accumbens and dentate gyrus.
Furthermore, ADX47273 blocked PCP, apomorphine and amphetamine-induced locomotor activities (MED = 100 mg/kg, IP) in mice, and decreased extracellular levels of dopamine in the nucleus accumbens, but not in the striatum, in rats.
Preferential enhancement of dopamine transmission within the nucleus accumbens (NAc) shell is a fundamental aspect of the neural regulation of cocaine reward.
Here, we examined the influence of DBS of the nucleus accumbens shell on cocaine priming-induced reinstatement of drug seeking, an animal model of relapse. During the reinstatement phase, DBS was administered bilaterally to the nucleus accumbens shell through bipolar stainless steel electrodes. DBS of the nucleus accumbens shell significantly attenuated the reinstatement of drug seeking precipitated by these higher cocaine doses. Together, these results suggest that DBS of the nucleus accumbens shell may be a potential therapeutic option in the treatment of severe cocaine addiction..
We also found that CMS altered AMPA receptor GluR1 subunit levels in the hippocampus and the nucleus accumbens of adult, but not young animals.
OBJECTIVES: The present study investigates the effects of injections of a specific N-methyl-D: -aspartic acid (NMDA) antagonist 3-[ (R)-2-carboxypiperazin-4-yl]-propyl-1-phophonic acid (CPP) into the prefrontal cortex (PFC) on the extracellular concentrations of dopamine and acetylcholine in the nucleus accumbens (NAc) and on motor activity in the freely moving rat.
Since 18-methoxycoronaridine (18-MC), a selective antagonist of alpha3beta4 nicotinic receptors, was previously shown to alter dopamine release in the nucleus accumbens in response to chronic injections of cocaine and morphine, this drug could be a promising therapy for abnormal eating behavior.
Venlafaxine significantly increased dopamine (DA) levels in the nucleus accumbens (NAc) and the substantia nigra and decreased DA turnover in the NAc.
However, NK3 receptors play a role in the regulation of cocaine-induced DA responses in the nucleus accumbens core and shell subregions. NK3 receptor agonism as well as antagonism potentiate cocaine's effects on nucleus accumbens DA subregions specifically, and modulate the acute behavioral effects of cocaine in rats and non-human primates (Callithrix penicillata).
We examined how an acute dopamine (DA) receptor blockade affects locomotor and brain (nucleus accumbens or NAcc), muscle and skin temperature responses to three arousing stimuli (procedure of sc injection, tail-pinch and social interaction with another male rat) and intravenous cocaine (1 mg/kg).
Furthermore, in vivo microdialysis showed that URB597 reduced nicotine-induced dopamine elevations in the nucleus accumbens shell, the terminal area of the brain's mesolimbic reward system.
This pathway originates in the ventral tegmental area (VTA) and terminates in the nucleus accumbens (NAcc) where dopamine is increased by nicotine but decreased during withdrawal.
Moreover, enhanced Fos expressions were found in the medial prefrontal cortex and the core of the nucleus accumbens after reactivation of the MA-CPP memory. nucleus accumbens shell, basolateral or lateral amygdala, in this regard, did not seem to be involved in retrieval of the MA-CPP memory. These results, taken together, suggest that the medial prefrontal cortex and the core of the nucleus accumbens are anatomical substrates responsible for reactivation of the MA-CPP memory..
It is well known that during the male rat sexual interaction different levels of arousal or sexual motivation are involved and that these motivational changes are associated with variations in the level of dopamine (DA); however, it is not yet known if these changes are associated with a different functionality of the nucleus accumbens (Acc) and Ventral Tegmental Area (VTA), neural structures that constitute the DA mesoaccumbens system.
Several brain structures, including the medial preoptic area (mPOA), the ventromedial nucleus of the hypothalamus (VMH), the amygdala (Me), and the nucleus accumbens (Acb) have been implicated in the control of female sexual behavior.
Much effort has been devoted in the preclinical addiction literature to understanding the phenomenon of sensitization, an enhanced dopaminergic response in the nucleus accumbens that occurs after repeated exposure to psychostimulant drugs.
A novel G protein modulator (Gpsm1/AGS3) was up-regulated in the rat nucleus accumbens core (NAcore) but not in other limbic nuclei during abstinence from operant EtOH self-administration.
Brain sections were collected from the medial prefrontal cortex (mPFC), dorsolateral frontal cortex (DFC), caudate putamen, nucleus accumbens, hippocampal CA1 and CA3 regions, and entorhinal cortex and processed for in-vitro receptor autoradiography.
As shown previously we found an increase in striatal dopamine levels after perindopril treatment, though this did not extend to the mesolimbic system with neurotransmitter levels unchanged in the hippocampus, nucleus accumbens and frontal cortex.
In synaptosomes of rat nucleus accumbens and striatum N/OFQ inhibited DA synthesis and tyrosine hydroxylase (TH) phosphorylation at Ser40 via NOP receptors coupled to inhibition of the cAMP/protein kinase A pathway. Immunofluorescence studies showed that N/OFQ preferentially inhibited phospho-Ser40-TH in nucleus accumbens shell and that in this subregion NOP receptors partly colocalized with either TH or DA D(1) receptor positive structures.
Amygdala, nucleus accumbens, caudate putamen and hippocampus tissues were dissected 30 minutes following the last injection and analyzed for phosphorylated and total Akt and GSK3(alpha & beta) protein levels using Western blot analysis. Phosphorylation of Akt on the threonine-308 residue was significantly reduced in the nucleus accumbens and increased in the amygdala after 1 day of cocaine treatment; however, these effects were not accompanied by a significant decrease in GSK3 phosphorylation. The findings in nucleus accumbens may reflect dopaminergic motor-stimulant activity caused by acute cocaine, whereas the effects in amygdala may be associated with changes in emotional state that occur after acute and chronic cocaine exposure..
The rewarding effects of drugs of abuse are thought to be dependent on the mesocorticolimbic dopamine system, which originates in the ventral tegmental area (VTA) and projects into the nucleus accumbens (NAC) and other forebrain regions.
To search for a colocalization of TH and VGLUT2 protein in axon terminals of these neurons, the nucleus accumbens of normal and 6-OHDA-lesioned P15 rats was examined by electron microscopy after dual immunocytochemical labeling. In normal rats, VGLUT2 protein was found in 28% of TH positive axon terminals in the core of nucleus accumbens.
The comparative distribution of LGR8 (receptor protein) was examined by autoradiography of [ (125)I]-human INSL3 binding sites, with high densities detected in the thalamus, especially in Pf, and in the entire striatum-the caudate putamen (CPmu), islands of Calleja, olfactory tubercle, nucleus accumbens-with lower levels in distinct layers of cerebral cortex.
Previous work in our laboratory has shown that food deprivation and food presentation produce different patterns of neuronal activity (as measured by c-Fos immunoreactivity) in the medial prefrontal cortex and nucleus accumbens of rats. Since the amygdala has been implicated in both motivational and reinforcement processes and has neuronal connections to both the prefrontal cortex and nucleus accumbens, it was of interest to assess amygdaloid c-Fos immunoreactivity during similar manipulations of food deprivation and presentation.
In light of the well-established role of the nucleus accumbens in mediating the effects of psychostimulants, these data suggest that the nigrostriatal pathway can act as a critical effector mechanism for the nucleus accumbens highlighting the importance of intrastriatal connectivity and providing insight into the functional architecture of the striatum.Neuropsychopharmacology advance online publication, 13 August 2008; doi:10.1038/npp.2008.117..
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.
In the present study, the effects of 6-hydroxydopamine lesions of nucleus accumbens core vs. We conclude that nucleus accumbens core and medial shell dopaminergic innervation exert segregated effects on rewarding and aversive effects of nicotine.
Conditional inhibition of ILK expression was established in the nucleus accumbens (NAc) core by microinjecting recombinant adeno-associated virus-carrying, tetracycline-on-regulated small interfering RNA which reversed the chronic cocaine-induced psychomotor sensitization, as well as the changes in protein kinase B Ser473 phosphorylation, dendritic density, and dendritic spine numbers locally.
Abstract The nucleus accumbens is critical for reward-guided learning and decision-making. We examined whether the human nucleus accumbens engages such a mechanism by recording electrophysiological activity directly from the accumbens of human patients undergoing deep brain stimulation surgery. Gamma-alpha synchronization may reflect an electrophysiological gating mechanism in the human nucleus accumbens, and the phase differences in gamma-alpha coupling may reflect a reward information coding scheme similar to phase coding..
Microinjection of the calcium/calmodulin-dependent protein kinase II (CaMKII) inhibitor KN-93 into the nucleus accumbens (NAcc) shell impairs expression of the sensitized locomotion and NAcc dopamine (DA) overflow normally observed in psychostimulant-exposed rats.
Zonisamide suppressed the tacrine-induced c-Fos expression in the cortex, the dorsal striatum, and the nucleus accumbens, which are involved in the architecture of the cortico-basal ganglia-thalamocortical circuits.
In vitro, SIB-1508Y increased dopamine (DA) release from slices of rat striatum, nucleus accumbens (NAc), olfactory tubercles (OT) and prefrontal cortices (PFC) in a concentration-dependent manner.
Numbers of PER1-labeled cells were rhythmic not only within the suprachiasmatic nucleus (SCN), the locus of the primary circadian clock in mammals, but also in the peri-suprachiasmatic region, the oval nucleus of the bed nucleus of the stria terminalis, the central amygdala, and the nucleus accumbens.
The discriminative stimulus properties of ethanol are functionally regulated by ionotropic GABA(A) and NMDA receptors in specific limbic brain regions including the nucleus accumbens, amygdala, and hippocampus, as determined by microinjection studies. In contrast, discrimination training altered the pattern of ethanol-induced Fos-IR in the nucleus accumbens (core), medial septum, and the hippocampus (dentate and CA3).
Cocaine is known to enhance nucleus accumbens dopamine (NAcc DA), to serve as a positive reinforcer and to produce negative effects, such as anxiety.
In addition, brain areas differentially activated in different strains are described (hippocampus, prefrontal cortex, nucleus accumbens, locus ceruleus).
Dopamine in the nucleus accumbens (NAc) is an important neurotransmitter for reward-seeking behaviors such as intracranial self-stimulation (ICSS), although its precise role remains unclear.
Consistent with the in vitro data and behavioral effects, peripheral administration of PRC200-SS (5 and 10 mg/kg i.p.) significantly increased extracellular levels of serotonin and norepinephrine in the medial prefrontal cortex, and of serotonin and dopamine in the core of nucleus accumbens, with reduction of levels of 3,4-dihydroxyphenylacetic acid, homovanillic acid, and 5-hydroxyindoleacetic acid compared with levels for saline control.
In this work we studied a possibility to changing handedness in rats by injection of a dopamine agonist into the nucleus accumbens.
Acute or chronic (0.4 mg/kg, sc, once daily for 2 weeks) administration of nicotine elicited increases in extracellular levels of dopamine, dopamine metabolites, norepinephrine, or serotonin in medial prefrontal cortex, nucleus accumbens shell, and core of rats. Pretreatment with NT69L (1 mg/kg, intraperitoneally, ip) administered 40 min before nicotine injection significantly attenuated the acute nicotine-evoked increases in norepinephrine levels in medial prefrontal cortex, dopamine and serotonin in nucleus accumbens shell. After chronic nicotine administration, pretreatment of NT69L markedly reversed the increase in dopamine levels in the nucleus accumbens core.
Considerable evidence implicates the mesolimbic dopamine (DA) system in the processing of nicotine's reinforcing properties, specifically the ventral tegmental area (VTA) and the terminal fields of VTA DAergic projections to the "core" (NAcore) and "shell" (NAshell) subdivisions of the nucleus accumbens (NAc).
Three hours after amphetamine injection, there was an increase of preprodynorphin mRNA in the caudate putamen and nucleus accumbens and D(3)R mRNA levels were increased in the nucleus accumbens of BDNF(+/-) and wildtype mice.
Meanwhile, the expression of NOS positive neurons in nucleus accumbens septi and dorsal striatum decreased in the Zusanli group. CONCLUSION: Catgut embedding at "Zusanli" (ST 36) can attenuate Morphine analgesic tolerance and reverse formation of locomotion sensitization induced by chronic Morphine administration, which are possibly related with inhibition of the expression of NOS positive neurons in nucleus accumbens septi and dorsal striatum..
Stress exposure increased BDNF mRNA levels in the ventral tegmental area (VTA) and nucleus accumbens (NAc) only in cocaine-experienced mice following a prolonged, but not acute, drug-free period.
While glutamate transmission onto dopamine cells in the ventral tegmental area undergoes transient plasticity important for establishing addiction-related behaviors, glutamatergic plasticity in the nucleus accumbens is critical for the expression of these behaviors.
The nucleus accumbens (NAc) is a critical element of the mesocorticolimbic system, a brain circuit implicated in reward and motivation.
We recently observed that adult rats pre-exposed to Delta-9-tetrahydrocannabinol (THC) during adolescence self-administered higher amounts of heroin and had selective impairments of the enkephalin opioid system within the nucleus accumbens (NAc) implicated in reward-related behavior.
Type 5 adenylyl cyclase (AC5) is highly concentrated in the dorsal striatum and nucleus accumbens (NAc), two brain areas which have been implicated in motor function, reward, and emotion.
Infusion of the Group II metabotropic glutamate receptor antagonist LY341495 into the medial prefrontal cortex enhanced glutamate release in this region, the nucleus accumbens and the ventral tegmental area in sensitized animals, compared to controls, following short-term withdrawal but not after long-term withdrawal.
We investigated the effect of PNS on basal and stimulated dopamine and noradrenaline output in the nucleus accumbens of freely moving adolescent and young adult rats (30-35 and 60-70 postnatal days respectively) because of the importance of this area in drug dependence and possibly in psychiatric disorders that are treated with drugs that act on dopamine and noradrenaline transmission.
Dopamine, corticosteroids, oxytocin, vasopressin, and opioids form the neurochemical substrate for pair bonding in areas like the nucleus accumbens, the prefrontal cortex, the piriform cortex, the medial preoptic area, the ventral tegmental area and the medial amygdala, among others.
We assessed the anatomical specificity of muscimol intra-MSDB self-administration by injecting this molecule into the nucleus accumbens (NAc).
It is known that the ventral tegmental area (VTA) is necessary for induction, and expression involves the nucleus accumbens (NAc).
Taken as a whole, we propose that behavioral sensitization to psychostimulant drugs is attributable, at least in part, to persistent activation of the ventral hippocampus-nucleus accumbens pathway, with the resultant increase in tonic DA neuron firing enabling an abnormally higher response to subsequent psychostimulant administration..
Furthermore, DOI and amperozide, but not ritanserin, reduced the haloperidol-induced catalepsy When animals were unilaterally radiofrequency lesioned in either caudate putamen (CP) or nucleus accumbens (NA), amperozide reduced both the ipsi- and contralateral turns in CP-lesioned, but reduced only ipsilateral turns in NA-lesioned rats.
In contrast, three consecutive doses of MDMA (20 mg/kg each) at 2-h intervals produced long-lasting dopamine and serotonin depletions in striatum, nucleus accumbens and prefrontal cortex.
The state ofperoxidation processes in the basal nuclei (the nucleus caudatus, globus pallidus, nucleus accumbens, amigdaloid complex) of the rat's brain under conditions of an altered photoperiod has been studied.
In rats, expression of conditioned fear response increased extracellular level of citrulline in the nucleus accumbens. Infusion of SCH-23390 into the nucleus accumbens exerted no long-term effect on the baseline citrulline level but attenuated the increase in the extracellar citrulline produced by the expression of the response.
At the maximum pain syndrome 3 weeks after the deafferentation, a reorganization of the brain electrical activity was observed in the limbic structures (hippocampus, amygdale, and nucleus accumbens), frontal cortex, and the caudate putamen.
Coherent activity of nucleus accumbens neurons which was a characteristic of interactions between nearby cells was assessed by the method of crosscorrelation. The results suggest an important role of systemic activity of neurons in the nucleus accumbens in the organization of the long-latency reaction pattern, characteristic of self-control behavior..
Microdialysis studies were carried out to evaluate changes in the extracellular levels of dopamine in the nucleus accumbens of A(2A) KO mice after morphine administration.Key results:The acute administration of morphine induced a similar enhancement of locomotor activity and antinociceptive responses in both genotypes.
RESULTS: Our results demonstrate altered reward pathway activation along the nucleus accumbens-hypothalamic-ventral tegmental area circuitry resulting from overexpression of DeltaFosB in the nucleus accumbens and striatal regions. Levels of phosphorylated cyclic adenosine monophosphate (cAMP) response element binding protein (pCREB), brain-derived neurotrophic factor (BDNF), and dopamine and cyclic adenosine monophosphate regulated phosphoprotein with a molecular mass of 32 kDa (DARPP-32) in the nucleus accumbens were reduced in DeltaFosB mice, suggestive of reduced dopamine signaling.
Such findings have figured importantly in recent theories of drug addiction proposing that sensitized nucleus accumbens (NAcc) dopamine (DA) overflow in particular acts in concert with other alterations in the neurochemistry of this nucleus to promote drug seeking and self-administration.
It is well known that the nucleus accumbens plays an important role in drug reinforcing effect and relapse. Here, we examined how nucleus accumbens neuronal excitability becomes affected in rats exposed to morphine using whole-cell patch-clamp recordings. Taken together, repeated morphine exposure and short-term withdrawal may reduce nucleus accumbens activity and output by modulating intrinsic membrane properties of its output neurons, which could be an important neuroadaptation process that mediates morphine addictive effect..
In the nucleus accumbens shell, the +/- genotype elevated basal dopamine levels.
There is accumulating evidence that the nucleus accumbens (NAc) plays an important role in the pathophysiology of depression.
We will review findings that suggest that the nucleus accumbens, orbitofrontal cortex, amygdala, insula and anterior cingulate cortex are involved evaluating both the potential rewards associated with performing a task, as well as assessing the energetical demands involved in task performance.
We investigated the roles of the core and shell subfields of the nucleus accumbens (NAc) in drug- or foot-shock-induced reactivation of extinguished conditioned place preference (CPP) in morphine-addicted rats.
The nonaggressive A/J mice exhibited higher DA utilization in the nucleus accumbens and prefrontal cortex, higher D1 receptor expression in the rostral pole of the accumbens, and lower D2 receptor expression throughout the accumbens, as compared with aggressive BALB/cJ mice.
per day for 5 days) of METH on rat behavior, DA transport by the DAT, DAT density, and inhibition of DA transport by METH in both the nucleus accumbens and striatum. In animals treated with METH, DA transport velocities were increased by 6.4% in the nucleus accumbens and decreased by 21% in the striatum. Western blots demonstrated that DAT density was unchanged in the nucleus accumbens of METH-treated animals, but striatal DAT density was decreased by 20%. Further studies investigating METH inhibition of DA transport found that in the nucleus accumbens of METH-treated animals, the IC(50) was shifted to a larger value (from 0.81 to 1.45 microM).
Norepinephrine (NE) and corticotropin-releasing factor (CRF) signaling in the extended amygdala, including the bed nucleus of the stria terminalis, shell of the nucleus accumbens, and central nucleus of the amygdala, are generally involved in behavioral responses to environmental and internal stressors.
In vivo microdialysis revealed that the methamphetamine-induced release of dopamine in the nucleus accumbens was exaggerated in the mutant mice, suggesting that enhanced mesolimbic dopaminergic transmission contributes to their hyperactivity phenotype.
It is well established that the behavioral sensitization is based on the augmentation of the mesocorticolimbic dopaminergic activity originating in the ventral tegmental area of the midbrain that project to the nucleus accumbens, the medial prefrontal cortex and other forebrain regions.
From the studies that clarify the responsible brain regions, the importance of the nucleus accumbens, prefrontal cortex and hippocampus is clarified.
Drugs of abuse including nicotine acutely modulate the activity of mesolimbic dopaminergic neurons, projecting from the ventral tegmental area of the midbrain to the nucleus accumbens (NAc).
In this study, the effects of quinpirole sensitization, with and without pre-treatment with Ro 41-1049, were determined on dopamine D2-like receptors in the nucleus accumbens and the striatum. Densities of [ 3H]spiperone- and [ 3H]quinpirole-labeled sites were both increased 32% in the nucleus accumbens of rats with demonstrated locomotor sensitization to quinpirole.
The reward system contains the ventral tegmental area, nucleus accumbens and ventral pallidum and finally sends information to the lateral hypothalamic area, the feeding center.
Cingulate, subcaudate, BA25/CgWM, amygdala, posterior hypothalamus, orbitofrontal cortex, nucleus accumbens, anterior limb of the internal capsule and dorsomedial thalamus were studied.
We further summarize evidence showing that impulsivity, a spontaneously occurring behavioural tendency in outbred rats that is associated with low dopamine D2/3 receptors in the nucleus accumbens, predicts both the propensity to escalate cocaine intake and the switch to compulsive drug seeking and addiction..
Reward-seeking behavior is controlled by neuronal circuits that include the basolateral nucleus of amygdala (BLA), medial prefrontal cortex (mPFC), nucleus accumbens (NAc) and ventral tegmental area.
The objective of the present study was to test the potential antidepressant activity of nucleus accumbens infusions of minocycline alone or combined with antidepressant drugs or with several glutamate receptor antagonists, using the time-sampling method in the FST. Likewise, systemic injections of desipramine (P<0.05), fluoxetine (P<0.05) or several glutamate receptor antagonists: EMQMCM (P<0.05), MTEP (P<0.05) or dizocilpine (P<0.05) combined with intra-nucleus accumbens infusions of vehicle produced antidepressant-like actions. The subthreshold dose of intra-nucleus accumbens infusions of minocycline combined with systemic injections of subthreshold doses of desipramine (P<0.05) or EMQMCM (P<0.05) or MTEP (P<0.05) or dizocilpine (P<0.05) produced antidepressant-like actions.
Adaptations in dopamine and glutamate neurotransmission in the nucleus accumbens (NAc) and medial prefrontal cortex (mPFC) seem to mediate psychostimulant-induced behavioral sensitization.
In the ventral forebrain, sucrose sham licking increased Fos in the bed nucleus of the stria terminalis, central nucleus of amygdala, and the shell of nucleus accumbens.
With the use of EEG source image we found three different neural patterns in aged individuals: (1) left hippocampus and midbrain in mild AD, (2) left lateral orbitofrontal gyrus, left nucleus accumbens, caudate nucleus, thalamus, posterior cinguli, right precuneous, right superior parietal lobe in MCI, and (3) right lateral-medial orbitofrontal gyrus, caudate nucleus, thalamus, right lateral occipitotemporal gyrus in elderly controls.
In contrast and at all the time points of extinction, binding to DAT was significantly enhanced in CONT animals when compared to SALINE and NON-CONT rats in different forebrain and mesencephalic regions, including the nucleus accumbens, ventral tegmental area or caudate putamen.
Analysis of neural activation across 39 brain regions using Fos immunohistochemistry showed the following results: (1) VEHICLE-SOCIAL and VEHICLE-ALONE groups did not differ in Fos expression, indicating that a social context per se did not affect Fos expression, (2) MDMA-treated groups showed significantly increased Fos expression relative to VEHICLE treated groups in 30 brain regions, (3) the MDMA-SOCIAL group showed augmented Fos expression relative to the MDMA-ALONE group in six brain regions including the caudate-putamen (medial), medial preoptic area, paraventricular thalamic nucleus, central amygdala, ventromedial hypothalamic nucleus, and the medial amygdala (posterodorsal), and (4) the MDMA-SOCIAL group (but not the MDMA-ALONE group) showed augmented Fos expression relative to the VEHICLE groups in the nucleus accumbens, ventral tegmental area and periaqueductal grey.
RESULTS: The correlation analysis between personality dimensions and opioid receptor availability showed a significant (P < 0.001) positive correlation between the scores of reward dependence and the BP of the bilateral ventral striatum with nucleus accumbens (z scores, 4.52 and 4.33, respectively).
Here, we review studies from our laboratory that examined nucleus accumbens (NAc) cell firing and rapid dopamine signaling using electrophysiological and electrochemical recordings in behaving rodents.
Others areas, like nucleus accumbens, striatum, and several cortical areas, also could operate in some contextual learning..
Cue-induced reinstatement of alcohol-seeking behavior was associated with a three to five-fold increase in p-ERK1/2 IR in the basolateral amygdala and nucleus accumbens shell.
Acute cocaine treatment significantly elevated OS markers in prefrontal cortex (PFC) and nucleus accumbens (NAc) in rats, both in slices and following a single cocaine injection, which corresponded with a decrease in total antioxidant capacity (TAC).
Agonists of the alpha7 nAChR improve memory and attentional properties and increase immediate early gene expression in the prefrontal cortex and the nucleus accumbens. We show that acute systemic administration of the alpha7 nAChR agonist SSR180711 (10 mg/kg) result in a significant increase in Fos protein levels in the shell of nucleus accumbens in wild-type mice, but has no effect in the transgene mice.
To study this phenomenon, we assessed how delta-9-tetrahydrocannabinol (THC), a primary psychoactive ingredient of marijuana, affects locomotor and brain (nucleus accumbens or NAcc), muscle and skin temperature responses to natural arousing stimuli (one-minute tail-pinch and one-minute social interaction with another male rat) and iv cocaine (1 mg/kg) in male rats.
Moderate staining occurred in the lateral posterior nucleus of the thalamus, superficial layers of neocortex, periaqueductal gray, substantia nigra, stria terminalis, nucleus accumbens shell and tegmental nucleus.
On the other hand, drugs selectively acting on dopaminergic transmission produced modest changes in extracellular DA in mPFC, and had no effect on the occipital or parietal cortex.Acute administration of morphine did not increase DA levels in the PFC (where NA is diminished), in contrast with augmented dopaminergic neuronal activity; moreover, during morphine withdrawal both DA and NA levels increased, in spite of a diminished dopaminergic activity, both increases being antagonised by clonidine but not quinpirole administration.Extensive 6-hydroxy dopamine lesion of the ventral tegmental area (VTA) decreases below 95% of control both intra- and extracellular DA and DOPAC in the nucleus accumbens, but only partially or not significantly in the mPFC and parietal cortex.The above evidence points to a common origin for NA and DA in the cerebral cortex and suggests the possible utility of noradrenergic system modulation as a target for drugs with potential clinical efficacy on cognitive functions..
Here, we assessed whether endogenous dopamine receptor stimulation in nucleus accumbens contributes to both appetitive behavior and fearful behavior that is generated in keyboard manner by local glutamate disruptions at different sites in medial shell. 6,7-Dinitroquinoxaline-2,3(1H,4H)-dione (DNQX) microinjections (450 ng) locally disrupt glutamate signals in <4 mm(3) of nucleus accumbens, and generate either desire or fear (or both) depending on precise rostrocaudal location in medial shell.
Psychoactive stimulants that activate the dopamine D(1) receptor (Drd1a) induce the rapid phosphorylation and activation of extracellular signal-regulated kinase 1/2 (ERK1/2) in neurons of the nucleus accumbens and ventral striatum.
In addition, elderly volunteers who learned to juggle showed transient increases in gray matter in the hippocampus on the left side and in the nucleus accumbens bilaterally..
In addition, this incubation period confers to the environment paired with morphine the ability to increase ERK phosphorylation in the shell (but not the core) of the nucleus accumbens. These data show that, following repeated morphine injections, a drug-free period induces context-dependent phosphorylation of ERK in a specific population of neurons within the nucleus accumbens shell.
Thus, in the present study we compared the effect of a single dose of ethanol (1 g/kg, i.p.) on the extracellular levels of monoamines measured by microdialysis in the shell of nucleus accumbens of University of Chile bibulous (UChB) and University of Chile Abstainer (UChA) rats, bred for 79 and 88 generations to prefer or reject ethanol, respectively.
Intracerebral microdialysis and high-performance liquid chromatography were used to demonstrate that the acquisition and execution of an emotional conditioned reflex in Sprague-Dawley rats are accompanied by increases in extracellular citrulline (a co-product of nitric oxide synthesis) levels in the nucleus accumbens. Injection of the selective NMDA glutamate receptor antagonist MK-801 (100 microM) into the nucleus accumbens significantly decreased the increase in extracellular citrulline seen in this structure on acquisition of the emotional conditioned reflex and completely blocked the increase induced by execution of the reflex. These data suggest that during the acquisition and execution of an emotional conditioned reflex, the glutamatergic input of the nucleus accumbens acts on NMDA receptors to stimulate nitric oxide production in this part of the brain..
Addiction to alcohol, nicotine and heroin were reported in conjunction with DBS of the nucleus accumbens (NAc).
OBJECTIVES: The objective of this study is to investigate the effects of chronic buprenorphine treatment on cocaine-induced activity and levels of glutamate and dopamine (DA) in the nucleus accumbens (NAc) in rats that were preexposed to cocaine or drug-naïve.
In this study we established conditional silencing of integrin-linked kinase (ILK) expression in Sprague-Dawley rat brain by microinjection of rAAV-2-carrying, Tet-On-regulated siRNA expression cassette into nucleus accumbens (NAc) core and induction with doxycycline.
After extinction training, cocaine (10 mg/kg, i.p.) primed reinstatement was assessed in rats pretreated with N-acetylcysteine (0-60 mg/kg, i.p.) in the presence or absence of the system xc- inhibitor (S)-4-carboxyphenylglycine (CPG; 0.5 microM; infused into the nucleus accumbens). On the reinstatement test day, we then acutely impaired system xc- in some of the rats by infusing CPG (0.5 microM) into the nucleus accumbens. Rats that had received N-acetylcysteine prior to daily self-administration sessions exhibited diminished cocaine-primed reinstatement; this effect was reversed by infusing the cystine-glutamate exchange inhibitor CPG into the nucleus accumbens. Collectively these data establish system xc- in the nucleus accumbens as a key mechanism contributing to cocaine-primed reinstatement..
Deactivations were found in the right nucleus accumbens and the right cerebellar hemisphere.
In particular, results revealed that in the nucleus accumbens, methamphetamine rapidly, but reversibly (within 24 h), decreased plasmalemmal dopamine transporter function, without effect on plasmalemmal dopamine transporter immunoreactivity. Noteworthy, the nucleus accumbens and hypothalamus did not display the persistent long-lasting striatal dopamine depletions caused by the stimulant.
Nicotine-induced effects on dopamine in the dorsal and ventral hippocampus (VH), prefrontal and medial temporal cortex, and superior cerebral peduncle were lower in the young than in adult, the same in the ventral tegmental area (VTA) and lateral septal nucleus (LS), and somewhat higher in the nucleus accumbens shell (NAccS).
cocaine (0.75, 1.5, and 3.0 mg/kg) significantly inhibited DA uptake in the nucleus accumbens of anesthetized rats within 5 s.
During the processing of gains in the late phase of learning, PTSD patients as compared to controls showed lower activation in the nucleus accumbens and the mesial PFC, critical structures in the reward pathway.
RATIONALE: The nucleus accumbens (NAC) is a functionally heterogeneous brain region with respect to its involvement in cocaine-seeking behavior triggered by drug-associated explicit conditioned stimuli, foot shock stress, or cocaine itself in the reinstatement animal model of drug relapse.
These dietary nutrients led to a significant activation in the forebrain regions including nucleus accumbens, hypothalamic area, and limbic system with different timings.
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). The present study investigated the effects of selective excitotoxic lesions of the nucleus accumbens shell or core subregion on appetitive elemental cue and context conditioning, shown previously to be dependent on the basolateral amygdala and hippocampus, respectively.
We also investigated gene expression in four important regions of the brain, the nucleus accumbens, striatum, hippocampus, and cingulated cortex, and analyzed the data by two clustering methods.
When the ability to use environmental information or external cues is lost as well, significant cell loss in the ventral tegmental area, with reduced DA-innervation of the mesocorticolimbic regions and the nucleus accumbens, must be suspected.
Procedures such as cingulotomy, hypothalamotomy, and resection of the substantia innominata and the nucleus accumbens have been described as a treatment for severe addictive disorders.
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