The effects of local perfusion of the ventral tegmental area (VTA) with N-methyl-D-aspartic acid (NMDA) on extracellular dopamine concentrations in the nucleus accumbens were investigated by using in vivo microdialysis in halothane anaesthetized rats. The electrophysiological response of VTA dopamine neurons to NMDA were also assessed in an in vitro rat ...
PubMed
Rats were implanted with recording electrodes aimed at the subiculum and nucleus accumbens. They were subsequently placed in a cylindrical environment, where they searched for locations where they would receive rewarding medial forebrain bundle stimulation. At times a tone was sounded, indicating that the reward location was in the center of the environment. Animals quickly ...
The nucleus accumbens is a key mediator of cocaine reward, but the distinct roles of the two subpopulations of nucleus accumbens projection neurons, those expressing dopamine D1 vs. D2 receptors, are poorly understood. We show that deletion of TrkB, the brain-derived neurotrophic factor (BDNF) receptor, selectively from D1+ or D2+ ...
PubMed Central
To study how hippocampal output signals conveying spatial and other contextual information might be integrated in the nucleus accumbens, tonically active accumbens neurons were recorded in three unrestrained rats as they performed spatial orientation tasks on an elevated round rotatable platform with four identical reward boxes ...
Spontaneous firing of ventral tegmental area (VTA) dopamine (DA) neurons provides ambient levels of DA in target areas such as the nucleus accumbens (NAc) and the prefrontal cortex (PFC). Here we report that the glial cell line-derived neurotrophic factor (GDNF), produced in one target region, the NAc, is retrogradely transported by DA ...
Neuron Report Coordinated Accumbal Dopamine Release and Neural Activity Drive Goal such as the nucleus accumbens (NAc). However, a direct role of dopamine in ICSS-mediated reward has been questioned that, at certain sites, the onset of anticipatory dopamine surges and changes in neuronal firing
E-print Network
In the cocaine self-administering rat, individual nucleus accumbens (NAcc) neurons exhibit phasic changes in firing rate within minutes and/or seconds of lever presses (i.e. slow phasic and rapid phasic changes, respectively). To determine whether neurons that demonstrate these changes during self-administration ...
Acute administration of antipsychotic drugs increases dopamine (DA) neuron activity and DA release via D2 receptor blockade. However, it is unclear whether the DA neuron activation produced by antipsychotic drugs is due to feedback from postsynaptic blockade or is due to an action on DA neuron autoreceptors. This was evaluated using ...
Mesoventromedial dopamine neurons projecting from the medial ventral tegmental area to the ventromedial shell of the nucleus accumbens play a role in attributing incentive salience to environmental stimuli that predict important events, and appear to be particularly sensitive to the effects of psychostimulant drugs. Despite the observation that these ...
The N-methyl-D-aspartate receptors (NMDARs) play a key role in synaptic plasticity, but it remains unclear whether the intrinsic-firing properties, another major determinant of the functional output of neurons, are regulated by activation of NMDARs. Here, we examine the effects of NMDAR activation on the intrinsic-firing properties of ...
NAc inactivation increases food intake, indicating that NAc neurons exert ongoing inhibition of feeding. We previously described a subpopulation of NAc neurons that pause during sucrose licking and proposed that the pause permits consumption. We tested this hypothesis by first recording NAc neurons during sucrose consumption, and then ...
The striatum is considered to be critical for the control of goal-directed action, with the lateral dorsal striatum (latDS) being implicated in modulation of habits and the nucleus accumbens thought to represent a limbic�motor interface. Although medium spiny neurons from different striatal subregions exhibit many similar properties, differential ...
Little is known regarding the involvement of the ventral pallidum (VP) in cocaine-seeking behavior, in contrast with considerable documentation of the involvement of its major afferent, the nucleus accumbens, over the past thirty years utilizing electrophysiology, lesion, inactivation, molecular, imaging, and other approaches. The VP is neuroanatomically positioned to ...
SummaryThe cellular mechanisms underlying pathological alcohol seeking remain poorly understood. Here, we show an enhancement of nucleus accumbens (NAcb) core action potential firing ex vivo after protracted abstinence from alcohol but not sucrose self-administration. Increased firing is associated with reduced small-conductance ...
Basal ganglia circuits are organized as parallel loops that have been proposed to compete in a winner-take-all fashion to determine the appropriate behavioral outcome. However, limited experimental support for strong lateral inhibition mechanisms within striatal regions questions this model. Here, stimulation of the prefrontal cortex (PFC) using naturally occurring bursty patterns inhibited ...
Given the increasing research emphasis on putative accumbal functional compartmentation, we sought to determine whether neurons that demonstrate changes in tonic firing rate during cocaine self-administration are differentially distributed across subregions of the NAcc. Rats were implanted with jugular catheters and microwire arrays targeting NAcc ...
Nicotine self-administration (SA) is maintained by several variables, including the reinforcing properties of nicotine-paired cues and the nicotine-induced amplification of those cue properties. The nucleus accumbens (NAc) is implicated in mediating the influence of these variables, though the underlying neurophysiological mechanisms are not yet understood. In the present ...
Orexin (ORX) plays a critical role in reward-seeking behavior for natural rewards and drugs of abuse. The mesolimbic dopamine (DA) pathway that projects into the nucleus accumbens (NAc) from the ventral tegmental area is deeply involved in the neural mechanisms underlying reward, drug abuse and motivation. A recent study demonstrated that ORX-immunopositive fibers densely ...
Dopamine (DA) neurons in the substantia nigra (SN) and ventral tegmental area (VTA) form several projection systems with diverse functions, such as motor planning through the striatum, reward seeking via the nucleus accumbens (NAc), and cognitive control through the prefrontal cortex (PFC). Disruptions in DA cell activity profoundly impair these functions ...
The shell division of the nucleus accumbens receives noradrenergic input from neurons in the nucleus of the solitary tract (NTS) that transmit information regarding fluctuations in peripheral hormonal and autonomic activity. Accumbens shell neurons also receive converging inputs from limbic areas such as the ...
The current study aimed to further elucidate the role of endocannabinoid signaling in methamphetamine-induced psychomotor activation. Rats were treated with bilateral, intracranial microinjections of the cannabinoid CB1 receptor antagonists rimonabant (1 ?g; 1 ?l) or AM251 (1 ?g; 1 ?l), or vehicle (1 ?l), followed by intravenous methamphetamine (3 mg/kg). Antagonist pretreatment in the nucleus ...
The cytoarchitecture and axonal projection pattern of pallial areas was studied in the fire-bellied toad Bombina orientalis by intracellular injection of biocytin into a total of 326 neurons forming 204 clusters. Five pallial regions were identified, differing in morphology and projection pattern of neurons. The rostral pallium ...
Extracellular single-unit recordings and iontophoresis were used to examine the effects of different selective sigma receptor ligands on dopaminergic and glutamatergic N-methyl-D-aspartate (NMDA) neurotransmissions both in origin (A10 and A9 areas) and terminal (nucleus accumbens and caudate nucleus) regions of the rat mesolimbic and nigrostriatal dopaminergic systems. The ...
Tobacco use is a major public health problem, and although many smokers report that they want to quit, only a small percentage succeed. Side effects associated with nicotine withdrawal, including depression, anxiety, and restlessness, certainly contribute to the low success rate. The dorsal raphe nucleus (DRN) is a serotonergic center with many functions, including control of mood and emotional ...
Simultaneous dopamine and single-unit recordings reveal accumbens GABAergic responses: Implications including dopamine and GABA. For this reason, the neurotransmitters that are central to this behavior and cyclic voltammetry at the same electrode in awake rats to simultaneously examine cell firing and dopamine
The lateral hypothalamus (LH) and the nucleus accumbens shell (AcbSh) are brain regions important for food intake. The AcbSh contains high levels of receptor for melanin-concentrating hormone (MCH), a lateral hypothalamic peptide critical for feeding and metabolism. MCH receptor (MCHR1) activation in the AcbSh increases food intake while AcbSh MCHR1 blockade reduces feeding. ...
The lateral hypothalamus and the nucleus accumbens shell (AcbSh) are brain regions important for food intake. The AcbSh contains high levels of receptor for melanin-concentrating hormone (MCH), a lateral hypothalamic peptide critical for feeding and metabolism. MCH receptor (MCHR1) activation in the AcbSh increases food intake, while AcbSh MCHR1 blockade reduces feeding. Here ...
Many motivated and addiction-related behaviors are sustained by activity of both dopamine D1- and D2-type receptors (D1Rs and D2Rs) as well as CB1 receptors (CB1Rs) in the nucleus accumbens (NAc). Here, we use in vitro whole-cell patch-clamp electrophysiology to describe an endocannabinoid (eCB)-dopamine receptor interaction in adult rat NAc core neurons. ...
The midbrain ventral tegmental area (VTA) projection to the nucleus accumbens (NAc) is implicated in motivation and reinforcement. A significant number of NAc medium spiny neurons (MSNs) project back to the VTA, although the nature of this projection is essentially unknown. For example, do NAc MSNs directly target accumbens-projecting ...
Nicotine is the primary psychoactive component of tobacco. Its reinforcing and addictive properties depend on nicotinic acetylcholine receptors (nAChRs) located within the mesolimbic axis originating in the ventral tegmental area (VTA). The roles and oligomeric assembly of subunit ?4- and subunit ?6-containing nAChRs in dopaminergic (DAergic) neurons are much debated. Using ...
Mesostriatal dopaminergic neurons and striatal cholinergic interneurons participate in signaling the motivational significance of environmental stimuli and regulate striatal plasticity. Dopamine (DA) and acetylcholine (ACh) have potent interactions within the striatum at multiple levels that include presynaptic regulation of neurotransmitter release and postsynaptic effects in ...
The nucleus accumbens (NAc) is a forebrain area in the mesocorticolimbic dopamine (DA) system that regulates many aspects of drug addiction. Neuronal activity in the NAc is modulated by different subtypes of DA receptors. Although DA signaling has received considerable attention, the mechanisms underlying D(2)-class receptor (D(2)R) modulation of ...
Lithium has been used extensively for mood stabilization, and it is particularly efficacious in the treatment of bipolar mania. Like other drugs used in the treatment of psychiatric diseases, it has little effect on the mood of healthy individuals. Our previous studies found that mice with a mutation in the Clock gene (Clock?19) have a complete behavioral profile that is very similar to human ...
The behavioral and motivational changes that result from use of abused substances depend upon activation of neuronal populations in the reward centers of the brain, located primarily in the corpus striatum in primates. To gain insight into the cellular mechanisms through which abused drugs reinforce behavior in the primate brain, changes in firing of ...
Multiple signals for reward-hedonic impact, motivation, and learned associative prediction-are funneled through brain mesocorticolimbic circuits involving the nucleus accumbens and ventral pallidum. Here, we show how the hedonic "liking" and motivation "wanting" signals for a sweet reward are distinctly modulated and tracked in this circuit separately from signals for ...
Neuregulin 1 (Nrg1), a schizophrenia susceptibility gene, is involved in fundamental aspects of neurodevelopment. Mice lacking any one of several isoforms of Nrg1 have a variety of schizophrenia-related phenotypes, including deficits in working memory and sensorimotor gating, loss of spines in pyramidal neurons in the ventral subiculum, loss of dendrites in cortical pyramidal ...
Although neuroadaptations in the nucleus accumbens (NAc) are thought to contribute to nicotine addiction, little is known about the chronic effects of nicotine on NAc neuronal activity. In the present experiment, rats were exposed to a 23-day period of nicotine self-administration (SA), a 30-day abstinence period, and a 7-day period of re-exposure to SA. ...
It is well known that the nucleus accumbens plays an important role in drug reinforcing effect and relapse. However, the cellular neuroadaptations that take place in accumbens neurons after repeated drug exposure are still not well understood, especially for opioids. Here, we examined how nucleus accumbens ...
The nucleus accumbens (NAc) is involved in many reward-related behaviors. The NAc has two major components, the core and the shell. These two areas have different inputs and outputs, suggesting that they contribute differentially to goal-directed behaviors. Using a discriminative stimulus (DS) task in rats and inactivating the NAc by blocking excitatory inputs with glutamate ...
The nucleus accumbens (NAc) plays a role in hedonic reactivity to taste stimuli. Learning can alter the hedonic valence of a given stimulus, and it remains unclear how the NAc encodes this shift. The present study examined whether the population response of NAc neurons to a taste stimulus is plastic using a conditioned taste aversion (CTA) paradigm. ...
ERIC Educational Resources Information Center
We describe a computational model of the principal cell in the nucleus accumbens (NAcb), the medium spiny projection (MSP) neuron. The model neuron, constructed in NEURON, includes all of the known ionic currents in these cells and receives synaptic input from simulated spike trains via NMDA, AMPA, and GABAA ...
Mesolimbic dopamine neurons projecting from the ventral tegmental area (VTA) to the nucleus accumbens (NAc) are part of a complex circuit mediating cocaine-directed behaviors. However, the precise role of rapid (subsecond) dopamine release within the primary sub-regions of the NAc, the core and shell, and its relationship to NAc cell ...
Neurochemical, electrophysiological and behavioural evidence indicates that certain forms of goal-directed behaviours are mediated by complex and reciprocal interactions between limbic and dopamine (DA) inputs in the nucleus accumbens (NAc). Mesoaccumbens DA transmission appears to be compartmentalized; synaptic DA transmission is mediated by phasic burst ...
... were made of the activity of single neurons in the olfactory bulbs of anesthetized ... produced an alteration in firing rate in some olfactory bulb neurons ...
DTIC Science & Technology
... When a neuron Page 3. is firing, it emits excitatory and inhibitory signals to the neurons around it. E represents a neuron's ...
Histaminergic neurons of the hypothalamic tuberomammillary nuclei (TMN) send projections to the whole brain. Early anatomical studies described histaminergic neurons as a homogeneous cell group, but recent evidence indicates that histaminergic neurons are heterogeneous and organized into distinct circuits. We addressed this issue using ...
Dopamine (DA) neurotransmission in the nucleus accumbens (NAc) is critically involved in normal as well as maladaptive motivated behaviors including drug addiction. Whether the striatal neuromodulator nitric oxide (NO) influences DA release in NAc is unknown. We investigated whether exogenous NO modulates DA transmission in NAc core and how this interaction varies depending on ...
Neuropharmacological profiles of 5-(2-[4-(6-fluoro-1H-indole-3-yl) piperidine-1-yl] ethyl)-4-(4-fluorophenyl) thiazole-2-carboxylic acid amide (NRA0562) in rats were examined using electrophysiological and immunohistochemical methods. The firing rates of the substantia nigra pars compacta (A9) and the ventral tegmental area (A10) dopamine neurons were ...
7-Hydroxy-N,N-di-n-propyl-2-aminotetralin (7-OH-DPAT), an agonist with relative selectivity for the dopamine D3 receptor, was examined in several electrophysiological assays to determine whether it exhibits preferential effects in the mesolimbic versus nigrostriatal dopamine systems. Extracellular single unit activities of substantia nigra pars compacta (A9) and ventral tegmental area (A10) ...
Neurons are able to communicate with each other using biochemicals called neurotransmitters. Use Virtual Neuron to explore neurotransmitter properties, make neurons fire, and manipulate neural circuits.
NSDL National Science Digital Library
Receptor-specific compounds were applied by retrograde microdialysis to the ventral tegmental area (VTA) of the rat brain. The effect of the intrategmental infusions on extracellular dopamine in the ipsilateral nucleus accumbens were recorded with a second microdialysis probe. Intrategmental infusion of muscimol (10-40 microM) or baclofen (50 microM) decreased extracellular ...
Aversive states are proposed to drive addiction. Here, Wheeler and colleagues show that drug-associated cues come to activate neural representations of aversive information in nucleus accumbens and that this activation predicts subsequent drug use. These remarkable data identify a potential neural substrate through which aversive affective representations may motivate drug ...
The notion of gating as a mechanism capable of controlling the flow of information from one set of neurons to another, has been studied in many regions of the central nervous system. In the nucleus accumbens, where evidence is especially clear, gating seems to rely on the action of bistable neurons, i.e., of ...
Dopaminergic afferents arising from the ventral tegmental area (VTA) are crucial elements in the neural circuits that mediate arousal, motivation, and reinforcement. Two major targets of these afferents are the medial prefrontal cortex (mPFC) and the nucleus accumbens (NAc). Whereas dopamine (DA) in the mPFC has been implicated in working memory and attentional processes, DA ...
Learned associations between effects of abused drugs and the drug administration environment play important roles in drug addiction. Histochemical and electrophysiological studies suggest that these associations are encoded in sparsely distributed nucleus accumbens neurons that are selectively activated by drugs and drug-associated cues. Although ...
In vivo microdialysis combined with HPLC-EC analysis was used to monitor extracellular glutamate in the n. accumbens of Sprague-Dawley rats during footshock and food delivery. The footshock presentation resulted in a delayed increase in extracellular glutamate level, whereas the food intake caused its decrease. The intra-accumbens infusion of glutamate ...
Reward intake optimization requires a balance between exploiting known sources of rewards and exploring for new sources. The prefrontal cortex (PFC) and associated basal ganglia circuits are likely candidates as neural structures responsible for such balance, while the hippocampus may be responsible for spatial/contextual information. Although studies have assessed interactions between hippocampus ...
Both hemispheric bias and sex differences exist in striatal-mediated behaviors and pathologies. The extent to which these dimorphisms can be attributed to an underlying neuroanatomical difference is unclear. We therefore quantified neuron soma size and density in the dorsal striatum (CPu) as well as the core (AcbC) and shell (AcbS) subregions of the nucleus ...
Animals learn which foods to ingest and which to avoid. Despite many studies, the electrophysiological correlates underlying this behavior at the gustatory-reward circuit level remain poorly understood. For this reason, we measured the simultaneous electrical activity of neuronal ensembles in the orbitofrontal cortex, insular cortex, amygdala and nucleus ...
Professor Christian Keysers explains the mirror neuron may be explained by the "what fires together, wires together" principle.
There is significant pharmacological and behavioral evidence that group I metabotropic glutamate receptors (mGluR1a and mGluR5) in the nucleus accumbens play an important role in the neurochemical and pathophysiological mechanisms that underlie addiction to psychostimulants. To further address this issue, we undertook a detailed ultrastructural analysis to characterize changes ...
The objective of these studies was to pharmacologically characterize the mechanism responsible for a folate-induced stimulation of locomotor activity in rats after bilateral injection into the nucleus accumbens region of the brain. Folic acid (FA) and 5-formyltetrahydrofolic acid (FTHF) produced this hypermotility response after intra-accumbens injection, ...
Energy Citations Database
--triggered average.triggered average. 2.2. In neurons firing periodically, the spike triggered average canIn neurons periodically, the spike triggered average canIn neurons firing periodically, the spike triggered average can.triggered average. 2.2. In neurons ...
... Title : Rhythmically Firing (20 - 50 Hz) Neurons in Monkey Primary Somatosensory Cortex: Activity Patterns during Initiation of Vibratory-Cued ...
The Stochastic Syncoder was developed as an element of an experimental communication system. However, its design was based on observed neuron activity, and in itself is able to simulate the firing of a neuron. This paper describes the hardware model, and ...
National Technical Information Service (NTIS)
There has been increasing interest in the ability of neuropeptides involved in feeding to modulate circuits important for responses to drugs of abuse. A number of peptides with effects on hypothalamic function also modulate the mesolimbic dopamine system (ventral tegmental area and nucleus accumbens). Similarly, common stress-related pathways can modulate food intake, drug ...
The present study was designed to determine if cannabinoids share with other drugs of abuse the ability to stimulate mesolimbic dopaminergic neurons and if this effect is mediated by cannabinoid receptors. To this end, the effects of the prototypical cannabinoid, delta9 tetrahydrocannabinol �(-)-trans-(6aR,10aR)-6a,7,8,10a-tetrahydro-6,6,9-trimethyl- ...
Neuronal circuits including medium spiny neurons (MSNs) in the nucleus accumbens (NAc) and melanin-concentrating hormone (MCH)-containing neurons in the lateral hypothalamic area (LHA) are hypothesized to play an important role in hedonic feeding. A reciprocal connection between NAc MSNs and MCH-containing ...
Conditions of increased cognitive or emotional demand activate dopamine release in a regionally selective manner. Whereas the brief millisecond response of dopamine neurons to salient stimuli suggests that dopamine�s influence on behaviour may be limited to signalling certain cues, the prolonged availability of dopamine in regions such as the prefrontal cortex and nucleus ...
The open channel N-methyl-D-aspartate (NMDA) receptor antagonists dizocilpine (MK-801) and phencyclidine (PCP) increase the firing rate of both A9 and A10 dopaminergic neurons in the rat. In the A10 nucleus, this effect of MK-801 is reportedly prevented by either competitive NMDA antagonists or serotonin2 (5-HT2) antagonists. The present study examined the ...
BackgroundDopamine signaling in the nucleus accumbens (NAc) is essential for goal-directed behaviors and primarily arises from burst firing of ventral tegmental area (VTA) neurons. However, the role of associative neural substrates such as the basolateral amygdala (BLA) in regulating phasic dopamine release in the NAc, particularly ...
Lesion of mesolimbic dopaminergic neurons induces hypoactivity and hypo-exploration in a new environment, lack of hyperactivity to amphetamine and hyperresponsiveness to apomorphine. Transplantation of embryonic dopaminergic cells from rat embryos into the deafferented nucleus accumbens restores, 8 weeks after grafting, some of the deficits obtained after ...
This study examined the effects of norepinephrine (NE) and phentolamine on the electrical activities of pain-excited neurons (PENs) and pain-inhibited neurons (PINs) in the nucleus accumbens (NAc) of Wistar rats. Trains of electric pulses applied to the right sciatic nerve were used to provide noxious stimulation, and the discharges of ...
Cholinergic neurons were studied by immunohistochemistry with an antiserum against human choline acetyltransferase in the caudate nucleus, putamen, and ventral striatum (including the nucleus accumbens) of three patients with Alzheimer disease and three control subjects. Immunoreactive cell bodies were mapped and counted. In the ventral striatum of ...
NASA Astrophysics Data System (ADS)
Beta-endorphin is an endogenous opioid peptide that has been hypothesized to be involved in the behavioral effects of drugs of abuse including psychostimulants. Using microdialysis, we studied the effect of cocaine on extracellular levels of beta-endorphin in the nucleus accumbens, a brain region involved in the reinforcing effects of psychostimulant drugs. ...
The mesoaccumbens dopamine system is intricately in-volved in the locomotor stimulation produced by cocaine and sensitization of this effect following repeated cocaine administration. The mechanisms responsible for the ex-pression of sensitized locomotion appear to involve alter-ations in both presynaptic (increased dopamine release) and postsynaptic (increased responsiveness of dopamine Dl ...
. Such aversive states are proposed to incline the addict toward further drug use (Koob and Le Moal, 2001; Solomon learn to avoid taste cues that are predictive of addictive drugs (Grigson and Twining, 2002; Wise et al@schoenbaumlab.org DOI 10.1016/j.neuron.2008.02.025 Aversive states are proposed to drive addiction. Here, Wheeler
Oxytocin regulates partner preference formation and alloparental behavior in the socially monogamous prairie vole (Microtus ochrogaster) by activating oxytocin receptors in the nucleus accumbens of females. Mating facilitates partner preference formation, and oxytocin-immunoreactive fibers in the nucleus accumbens have been described in prairie voles. ...
