Hippocampus VTA Amygdala

Approximately 14.4 million Americans are experiencing alcohol use disorder (AUD) and about two-thirds of people who experience drug addiction will relapse, highlighting the need to develop novel and effective treatments. Glucagon-like peptide-1 (GLP-1) is a peptide hormone implicated in the mesocorticolimbic reward system and has become a peptide of interest with respect to its putative inhibitory effects on drug reward. In order to further develop treatments for those diagnosed with AUD, the interplay between GLP-1 receptor signaling and ethanol consumption must be elucidated...

Photobiomodulation (PBM) or the use of red to near-infrared irradiation spectrum, is a non-invasive intervention that produces neurostimulatory effects and reaches benefits in several pathologies as well as in healthy subjects. The main objective of this study was to evaluate and compare the effects of PBM in a rat brain network on basal state and functional activity during the execution of a reversal task. Twenty-eight rats were divided into four groups: control group (n = 7), control photobiomodulation group (n = 8), behavioural group (n = 6) and behavioural photobiomodulation group (n = 7)...

The development of current neuroleptics was largely aiming to decrease excessive dopaminergic signaling in the striatum. However, the notion that abnormal dopamine creates psychotic symptoms by causing an aberrant assignment of salience that drives maladaptive learning chronically during disease development suggests a therapeutic value of early interventions that correct salience-related neural processing. The mesolimbic dopaminergic output is modulated by several interconnected brain-wide circuits centrally involving the hippocampus and key relays like the ventral and associative striatum, ventral pallidum, amygdala, bed nucleus of the stria terminalis, nucleus reuniens, lateral and medial septum, prefrontal and cingulate cortex, among others...

Opioid Use Disorder (OUD) is a chronic relapsing clinical condition with tremendous morbidity and mortality that frequently persists, despite treatment, due to an individual's underlying psychological, neurobiological, and genetic vulnerabilities. Evidence suggests that these vulnerabilities may have neurochemical, cellular, and molecular bases. Key neuroplastic events within the mesocorticolimbic system that emerge through chronic exposure to opioids may have a determinative influence on behavioral symptoms associated with OUD...

The state-dependent memory defines as a state that the retrieval of recently obtained information may be potential if the subject exists in a similar physiological situation as for the period of the encoding stage. Studies revealed that exogenous and endogenous compounds could induce state-dependent memory. The state-dependent memory made it probable to differentiate the effects of drugs per se on learning from the effects due to alterations in drug state during the task. Studies proposed the role of regions beyond the limbic formation and illustrated that state-dependent memory produced by various neurotransmitter systems and pharmacological compounds...

Ultrasonic vocalizations are important for coordinating social behavior in rats. Examination of the neurochemical mechanisms that govern social behavior and ultrasonic vocalization emission is crucial for understanding the social impairments that occur in many neuropsychiatric disorders. To elucidate neurochemical changes in the brain structures related to social behavior and their mutual relationships, we conducted three-phase experiment. Neurochemicals were measured in the following behavioral situations: without social encounter, with short social encounter, with long social encounter in isolated and non-isolated rats...

AIMS: The appetite regulating hormone leptin, which is mainly secreted from adipose tissue, is an important regulator of food intake and modulator of reward-driven behavior. Leptin exerts its biological actions via binding to the leptin receptor, which is expressed in the hypothalamus, but also in the hippocampus, the amygdala and the substantia nigra. In the ventral tegmental area (VTA), leptin attenuates the firing rate of dopaminergic neurons that project to the Nucleus accumbens (NAc), which serves as relay to other brain areas of the "addiction network", such as the prefrontal cortex...

Neuromodulatory regions that detect salience, such as amygdala and ventral tegmental area (VTA), have distinct effects on memory. Yet, questions remain about how these modulatory regions target subregions across the hippocampus and medial temporal lobe (MTL) cortex. Here, we sought to characterize how VTA and amygdala subregions (i.e., basolateral amygdala and central-medial amygdala) interact with hippocampus head, body, and tail, as well as cortical MTL areas of perirhinal cortex and parahippocampal cortex in a task-free state...

BACKGROUND: Oxytocin (OXT), shown to decrease food intake in animal models and men, is a promising novel treatment for obesity. We have shown that in men with overweight and obesity, intranasal (IN) OXT reduced the functional magnetic resonance imaging (fMRI) blood oxygenation level-dependent signal in the ventral tegmental area (VTA), the origin of the mesolimbic dopaminergic reward system, in response to high-calorie food vs. nonfood images. Here, we employed functional connectivity fMRI analysis, which measures the synchrony in activation between neural systems in a context-dependent manner...

The mesocorticolimbic system is comprised of dopaminergic neurons in the ventral tegmental area (VTA) and their projection targets in the ventral striatum, amygdala, prefrontal cortex, and hippocampus, among others. Regulation of dopamine transmission within this system is achieved in part through a negative feedback mechanism via dopamine D2 autoreceptors located on somatodendrites and terminals of VTA dopaminergic neurons. Dysregulation of this mechanism has been implicated in addiction and other psychiatric disorders, although the biological bases for these associations are unclear...

We examine synaptic connectivity and cocaine-evoked plasticity at specific networks within the nucleus accumbens (NAc). We identify distinct subpopulations of D1+ medium spiny neurons (MSNs) that project to either the ventral pallidum (D1+VP ) or the ventral tegmental area (D1+VTA ). We show that inputs from the ventral hippocampus (vHPC), but not the basolateral amygdala (BLA), are initially biased onto D1+VTA MSNs. However, repeated cocaine exposure eliminates the bias of vHPC inputs onto D1+VTA MSNs, while strengthening BLA inputs onto D1+VP MSNs...

18 F-labeled fluorodeoxyglucose positron emission tomography (18 F-FDG PET) is the most sensitive tool for studying brain metabolism in vivo. We investigated the image patterns of 18 F-FDG PET during reperfusion injury and correlated changes of whole brain blood flow utilizing a rat myocardial ischemia/reperfusion injury (MIRI) model. The results assessed by echocardiography indicated resultant cardiac dysfunction after ischemia-reperfusion in the rat heart. It was found that the average standardized uptake value (SUVaverage ) of the whole brain was significantly decreased in model rats, and the glucose uptake of different brain regions including accumbens core/shell (Acb), left caudate putamen (LCPu), hippocampus (HIP), left hypothalamus (LHYP), olfactory (OLF), superior colliculus (SC), right midbrain (RMID), ventral tegmental area (VTA), inferior colliculus (IC) and left thalamus whole (LTHA) was significantly decreased in MIRI rats whereas no significant difference was found in the SUVaverage of amygdala (AMY), right CPu, RHYP, right HYP, left MID, right THA, pons and medulla oblongata (MO)...

Mild traumatic brain injury (MTBI) results in persistent deficits in the cognitive and emotive abilities governed by the mesocorticolimbic (MCL) neurocircuitry. In this study, we observed regional variations in the mitochondrial DNA copy number (mtDNAcn) in the MCL neurocircuitry. Although repeated MTBI (rMTBI) is known to cause mitochondrial dysfunction, the persistent changes in the mtDNAcn and its manifestations in 16S rRNA levels in the MCL neurocircuitry have not been investigated. Herein, we employed the closed head weight drop paradigm to induce rMTBI in rats...

Astrocytic connexin dysfunction is closely associated with synaptic impairment and contributes to the pathological development of depressive-like behaviours. However, little is known about the expression of connexins in astrocytes from different brain regions, or how tissue specific connexin expression affects local neuronal activity. Here, we established a mouse model of chronic social defeated stress (CSDS), from which we isolated astrocytes from the medial prefrontal cortex (mPFC), hippocampus, amygdala, and ventral tegmental area (VTA)...

Music is frequently used to establish atmosphere and to enhance/alter emotion in dramas and films. During music listening, visual imagery is a common mechanism underlying emotion induction. The present functional magnetic resonance imaging (fMRI) study examined the neural substrates of the emotional processing of music and imagined scene. A factorial design was used with factors emotion valence (positive; negative) and music (withoutMUSIC: script-driven imagery of emotional scenes; withMUSIC: script-driven imagery of emotional scenes and simultaneously listening to affectively congruent music)...

Cues signaling trust and dominance are crucial for social life. Previous studies on the effects of oxytocin (OT) nasal sprays on trustworthiness evaluations have been inconsistent and its influence on dominance is unknown. Vasopressin (AVP) may also influence social cue perception, but even fewer investigations have evaluated this possibility. We evaluated the effects of intranasal OT and AVP compared to placebo control during three double-blinded functional magnetic resonance imaging sessions. Twenty males received a pseudo-randomized order of nasal spray conditions and rated the trustworthiness and dominance of neutral faces...

Dopamine (DA) neurons in the ventral tegmental area (VTA) are well-known components of the brain involved in reward-related behaviors and participate in the generation of new memories. Much attention has been focused to understand how DA neurons integrate a diversity of afferent signals with local excitatory and inhibitory influences regulated by somatodendritic release of dopamine. However, the mechanisms that actively forget rewarding information are still terra incognita. Using rodents in the conditioned place preference (CPP) behavioral task, we show that during acquisition D1-type DA receptors (D1R) in the VTA are crucial components of a neural circuit involving the hippocampus that induces active forgetting of cocaine-associated long-term memory, while VTA and nucleus accumbens (NAc) D1R are required for its formation...

The nucleus accumbens (NAc) is the major component of the ventral striatum that regulates stress-induced depression. The NAc receives dopaminergic inputs from the ventral tegmental area (VTA), and the role of VTA-NAc neurons in stress response has been recently characterized. The NAc also receives glutamatergic inputs from various forebrain structures including the prelimbic cortex (PL), basolateral amygdala (BLA), and ventral hippocampus (vHIP), whereas the role of those glutamatergic afferents in stress response remains underscored...

Ephedrine is thought to exert behavioural effects primarily through actions on the central nervous system. However, the neuromechanism underlying the effects of ephedrine addiction still remains unclear. Our study aimed to establish chronic ephedrine addiction models in rhesus monkeys and to investigate the neuromechanism of chronic ephedrine addiction using the behavioural methods combined with resting-state blood oxygenation level dependent-functional magnetic resonance imaging (BOLD-fMRI). Monkeys in the ephedrine addiction group (n = 6) received intramuscular injections of ephedrine using a dose escalation method, with a chronic model established in 8 weeks, while in the control group (n = 4), monkeys received a pure 0...

A growing body of research provides compelling evidence that in rats 50-kHz USVs are a form of expression of positive emotions. Context-induced 50-kHz USVs emission is variable among rats, indicating individual differences in contextual response bound up with pharmacological reward. The aims of this study were to: extract the most important neurotransmitters related to context-induced conditioned 50-kHz USVs response; find biological basis of existing inter-individual differences in context-induced conditioned 50-kHz USVs response; create a model of all-to-all neurotransmitters correlations...