Search results for "nucleus accumbens"
showing 10 items of 94 documents
Assessment of the abuse potential of MDMA in the conditioned place preference paradigm: Role of CB1 receptors
2013
Numerous reports have highlighted the role of the endocannabinoid system in the addictive potential of MDMA (3,4-methylenedioxy-methamphetamine). A previous report showed that CB1 knockout (KOCB1) mice do not acquire MDMA self-administration, despite developing conditioned place preference (CPP). This contradiction could be due to the particular procedure of place conditioning used. The present work compares MDMA-induced CPP in KOCB1 mice using unbiased and biased procedures of place conditioning. In the unbiased procedure, MDMA induced CPP and reinstatement of the extinguished preference in wild type (WT) mice, but not in KOCB1 mice. In contrast, in a biased protocol of CPP, MDMA produced …
Molecular adaptations of the blood–brain barrier promote stress resilience vs. depression
2020
Significance Thirty to fifty percent of depressed individuals are unresponsive to commonly prescribed antidepressant treatments, suggesting that biological mechanisms, such as stress-induced inflammation and blood vessel dysfunction, remain untreated. The blood–brain barrier is the ultimate frontier between the brain and harmful toxins or inflammatory signals circulating in the blood. Depression and vulnerability to chronic social stress are associated with loss of this barrier integrity; however, the mechanisms involved remain poorly understood. Identification of adaptations leading to resilience under stressful conditions could help develop novel treatments. Here we combined behavioral, p…
Reward for food odors: An fMRI study of liking and wanting as a function of metabolic state and BMI
2014
Brain reward systems mediate liking and wanting for food reward. Here, we explore the differential involvement of the following structures for these two components: the ventral and dorsal striatopallidal area, orbitofrontal cortex (OFC), anterior insula, and anterior cingulate. Twelve healthy female participants were asked to rate pleasantness (liking of food and non-food odors) and the desire to eat (wanting of odor-evoked food) during event-related functional magnetic resonance imaging (fMRI). The subjective ratings and fMRI were performed in hunger and satiety states. Activations of regions-of-interest were compared as a function of task (liking vs. wanting), odor category (food vs. non-…
Efferent connections of the "olfactostriatum": a specialized vomeronasal structure within the basal ganglia of snakes.
2005
Abstract The olfactostriatum is a portion of the basal ganglia of snakes that receives substantial vomeronasal afferents through projections from the nucleus sphericus. In a preceding article, the olfactostriatum of garter snakes (Thamnophis sirtalis) was characterized on the basis of chemoarchitecture (distribution of serotonin, neuropeptide Y and tyrosine hydroxylase) and pattern of afferent connections [Martinez-Marcos, A., Ubeda-Banon, I., Lanuza, E., Halpern, M., 2005. Chemoarchitecture and afferent connections of the “olfactostriatum”: a specialized vomeronasal structure within the basal ganglia of snakes. J. Chem. Neuroanat. 29, 49–69]. In the present study, its efferent connections …
Induction of brain CYP2E1 changes the effects of ethanol on dopamine release in nucleus accumbens shell.
2009
CYP2E1 is an important enzyme involved in the brain metabolism of ethanol that can be induced by chronic consumption of alcohol. Recent works have highlighted the importance of this system in the context of the behavioural effects of ethanol. Unfortunately, the underlying neurochemical events for these behavioural changes, has not been yet explored. In this work, we have started this exploration by analyzing the possible changes in the neurochemical response of the mesolimbic system to ethanol after pharmacological induction of brain CYP2E1. We have used the dopamine extracellular levels in nucleus accumbens (NAc) core and shell, measured by means of microdialysis in vivo, as an index of th…
Local salsolinol modulates dopamine extracellular levels from rat nucleus accumbens: shell/core differences.
2008
Salsolinol (SAL), a condensation product of dopamine and acetaldehyde that appears in the rat and human brain after ethanol ingestion, has been largely implicated in the aetiology of alcoholism. Although the behavioural consequences of systemic or intracerebral SAL administrations have been described, the neurochemical effects of pharmacologically relevant doses of SAL and other tetrahydroisoquinolines (THIQs) in the brain areas involved in alcohol addiction are practically unknown. To gain an insight into this topic, male Wistar rats were stereotaxically implanted with one concentric microdialysis probe in either the shell or the core of the nucleus accumbens (NAc). Treatments involved loc…
Influence of the amount of food ingested on mesolimbic dopaminergic system activity: a microdialysis study.
1996
Abstract The mesolimbic dopaminergic system (MDS) has been shown to be activated by ingestive behaviors, and it has been suggested that this activation may be related to the rewarding properties of foods. Because rats eat more when given a more palatable diet, this study was undertaken to determine the relationship between the amount of food ingested and DA release in the nucleus accumbens of freely moving rats. The extracellular levels of dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) were measured by high-performance liquid chromatography with electrochemical detection on microdialysis samples from the nucleus accumbens. Each rat underwent three microdia…
Induction of conditioned place preference and dopamine release by salsolinol in posterior VTA of rats: involvement of μ-opioid receptors.
2011
Salsolinol (Sal), locally administered into the posterior VTA (pVTA) of rats, produces psychomotor responses and reinforcing effects, probably, through the activation of μ-opioid receptors (MORs). The neurochemical correlates of these phenomena are, however, practically unknown. In this paper, we explore the neurochemical events and the mechanisms involved in these behaviors. To do that, we test the ability of Sal, directly microinjected into the pVTA, to induce conditioned place preference (CPP) and to increase dopamine levels in the nucleus accumbens shell. Bilateral injections of 30 pmol of Sal induced a strong CPP (rats spent around 70% of the total test time), a result that could be ex…
Dose-dependent induction of CPP or CPA by intra-pVTA ethanol: Role of mu opioid receptors and effects on NMDA receptors.
2020
AbstractThe neurobiological mechanisms underlying alcohol motivational properties are still not fully understood, however, the mu-opioid receptors (MORs) have been evidenced as central elements in the manifestation of the alcohol reinforcing properties. Drug-associated environmental stimuli can trigger alcohol relapse and promote alcohol consumption whereby N-methyl-D-aspartate (NMDA) receptors play a pivotal role. Here we sought to demonstrate, for the first time, that ethanol induces conditioned place preference or aversion (CPP or CPA) when administered locally into the ventral tegmental area (VTA) and the associated role of MORs. We further analyzed the changes in the expression and mRN…
Acamprosate blocks the increase in dopamine extracellular levels in nucleus accumbens evoked by chemical stimulation of the ventral hippocampus.
2003
Recently, we have shown that acamprosate is able to modulate extracellular dopamine (DA) levels in the nucleus accumbens (NAc) and may act as an antagonist of N-methyl-D-aspartate (NMDA) receptors. Neurochemical studies show that chemical stimulation (using NMDA) of the ventral subiculum (vSub) of the hippocampus produces robust and sustained increases in extracellular DA levels in the NAc, an effect mediated through ionotropic glutamate (iGlu) receptors. The present study examines whether acamprosate locally infused in the NAc of rats could block or attenuate the increase in NAc extracellular DA elicited by chemical stimulation (with 5 mM NMDA) of the ventral subiculum of the hippocampus. …