The Adenosine A2A Receptor Activation in Nucleus Accumbens Suppress Cue-Induced Reinstatement of Propofol Self-administration in Rats

AbstractPropofol has shown strong addictive properties in rats and humans. Adenosine A2A receptors (A2AR) in the nucleus accumbens (NAc) modulate dopamine signal and addictive behaviors such as cocaine- and amphetamine-induced self-administration. However, whether A2AR can modulate propofol addiction remains unknown. AAV-shA2AR was intra-NAc injected 3 weeks before the propofol self-administration training to test the impacts of NAc A2AR on establishing the self-administration model with fixed ratio 1 (FR1) schedule. Thereafter, the rats were withdrawal from propofol for 14 days and tested cue-induced reinstatement of propofol seeking behavior on day 15. The propofol withdrawal rats received one of the doses of CGS21680 (A2AR agonist, 2.5–10.0 ng/site), MSX-3 (A2AR antagonist, 5.0–20.0 μg/site) or eticlopride (D2 receptor (D2R) antagonist, 0.75–3.0 μg/site) or vehicle via intra-NAc injection before relapse behavior test. The numbers of active and inactive nose-poke response were recorded. Focal knockdown A2AR by shA2AR did not affect the acquisition of propofol self-administration behavior, but enhance cue-induced reinstatement of propofol self-administration compared with the AAV-shCTRLgroup. Pharmacological activation of the A2AR by CGS21680 (≥ 5.0 ng/site) attenuated cue-induced reinstatement of propofol self-administration behavior. Similarly, pharmacological blockade of D2R by eticlopride (0.75–3.0 μg/site) attenuated propofol seeking behavior. These effects were reversed by the administration of MSX-3 (5.0–20.0 μg/site). The A2AR- and D2R-mediated effects on propofol relapse were not confounded by the learning process, and motor activity as the sucrose self-administration and locomotor activity were not affected by all the treatments. This study provides genetic and pharmacological evidence that NAc A2AR activation suppresses cue-induced propofol relapse in rats, possibly by interacting with D2R.

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2Hz-Electroacupuncture Attenuates Conditioned Cue-Evoked Heroin-Seeking Behavior and Increase CB2-Rs Expression in Relapse-Relevant Brain Regions in Heroin-Addicted Rats

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.998-999.164 ◽

2014 ◽

Vol 998-999 ◽

pp. 164-168 ◽

Cited By ~ 2

Author(s):

Lin Chen ◽

Bao Miao Ma ◽

Kai Yue ◽

Qin Ru ◽

Xiang Tian ◽

...

Keyword(s):

Prefrontal Cortex ◽

Nucleus Accumbens ◽

Rat Model ◽

Fixed Ratio ◽

Brain Regions ◽

Inhibitory Effect ◽

Control Group ◽

Self Administration ◽

Seeking Behavior

In order to investigate the influence of electroacupuncture on heroin seeking behavior and the expression of CB2-Rs in the relapse-relevant brain regions, heroin self-administration rat model which represents the heroin relapse behaviors was developed with progressive fixed ratio program. The model rats were randomly divided into 3 groups: control group, heroin-addicted group and 2Hz electroacupuncture group (stimulating on acupoints zusanli and sanyinjiao). The expression of CB2-Rs in the relapse-relevant brain regions were assessed with immunohistochemistry technologies. The reinstatement of heroin seeking behavior induced by conditioned cue priming showed that compared with the heroin-addicted group, active pokes in the 2Hz electroacupuncture group decreased significantly (p<0.05). Compared with the control group, the expression of CB2-Rs in prefrontal cortex (PFC) and nucleus accumbens (NAc) was significantly decreased (p<0.05) in heroin-addicted group and increaseed significantly recover (p<0.05) in the 2Hz electroacupuncture group. Our present results showed that 2Hz-electroacupuncture could attenuate the conditioned cue-evoked heroin-seeking behavior and the inhibitory effect was mediated partially by the increase CB2-Rs expression in relapse-relevant brain regions in heroin-addicted rats.

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Self-administration of intravenous amphetamine: effect of nucleus accumbens CCK B receptor activation on fixed-ratio responding

Psychopharmacology ◽

10.1007/s002130051176 ◽

1999 ◽

Vol 147 (3) ◽

pp. 331-334 ◽

Cited By ~ 6

Author(s):

D. E. A. Bush ◽

N. J. DeSousa ◽

F. J. Vaccarino

Keyword(s):

Nucleus Accumbens ◽

Fixed Ratio ◽

Receptor Activation ◽

Self Administration ◽

Fixed Ratio Responding

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Dopaminylation in Psychostimulant use Disorder Protects Against Psychostimulant Seeking Behavior by Normalizing Nucleus Accumbens (NAc) Dopamine Expression

Current Psychopharmacologye ◽

10.2174/2211556009666210108112737 ◽

2021 ◽

Vol 09 ◽

Author(s):

Kenneth Blum ◽

Mark S Gold ◽

Jean L. Cadet ◽

David Baron ◽

Abdalla Bowirrat ◽

...

Keyword(s):

Nucleus Accumbens ◽

Histone H3 ◽

D2 Receptor ◽

Reward Processing ◽

Allelic Polymorphism ◽

Cocaine Withdrawal ◽

Src Signaling ◽

Chronic Cocaine ◽

Cocaine Seeking ◽

Seeking Behavior

Background: Repeated cocaine administration changes histone acetylation and methylation on Lys residues and Deoxyribonucleic acid (DNA) within the nucleus accumbens (NAc). Recently Nestler’s group explored histone Arg (R) methylation in reward processing models. Damez-Werno et al. (2016) reported that during investigator and selfadministration experiments, the histone mark protein-R-methyltransferase-6 (PRMT6) and asymmetric dimethylation of R2 on histone H3 (H3R2me2a) decreased in the rodent and cocaine-dependent human NAc. Overexpression of PRMT6 in D2-MSNs in all NAc neurons increased cocaine seeking, whereas PRMT6 overexpression in D1-MSNs protects against cocaine-seeking. Hypothesis: Hypothesizing that dopaminylation (H3R2me2a binding) occurs in psychostimulant use disorder (PSU), and the binding inhibitor Srcin1, like the major DRD2 A2 allelic polymorphism, protects against psychostimulant seeking behavior by normalizing nucleus accumbens (NAc) dopamine expression. Discussion: Numerous publications confirmed the association between the DRD2 Taq A1 allele (30-40 lower D2 receptor numbers) and severe cocaine dependence. Lepack et al. (2020) found that acute cocaine increases dopamine in NAc synapses, results in histone H3 glutamine 5 dopaminylation (H3Q5dop), and consequent inhibition of D2 expression. The inhibition increases with chronic cocaine use and accompanies cocaine withdrawal. They also found that the Src kinase sig-naling inhibitor 1 (Srcin1 or p140CAP) during cocaine withdrawal reduced H3R2me2a binding. Consequently, this inhibited dopaminylation induced a “homeostatic brake.” Conclusion: The decrease in Src signaling in NAc D2-MSNs, like the DRD2 Taq A2 allele, a well-known genetic mechanism protective against SUD normalized nucleus accumbens (NAc) dopamine expression and decreased cocaine reward and motivation to self-administer cocaine. The Srcin1 may be an important therapeutic target.

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Sex Differences in Escalated Methamphetamine Self-Administration and Altered Gene Expression Associated With Incubation of Methamphetamine Seeking

The International Journal of Neuropsychopharmacology ◽

10.1093/ijnp/pyz050 ◽

2019 ◽

Vol 22 (11) ◽

pp. 710-723 ◽

Cited By ~ 8

Author(s):

Atul P Daiwile ◽

Subramaniam Jayanthi ◽

Bruce Ladenheim ◽

Michael T McCoy ◽

Christie Brannock ◽

...

Keyword(s):

Sex Differences ◽

Nucleus Accumbens ◽

Fixed Ratio ◽

Female Rats ◽

Male Rats ◽

Mrna Levels ◽

Self Administration ◽

Male And Female ◽

Orexin Receptors ◽

Male And Female Rats

Abstract Background Methamphetamine (METH) use disorder is prevalent worldwide. There are reports of sex differences in quantities of drug used and relapses to drug use among individuals with METH use disorder. However, the molecular neurobiology of these potential sex differences remains unknown. Methods We trained rats to self-administer METH (0. 1 mg/kg/infusion, i.v.) on an fixed-ratio-1 schedule for 20 days using two 3-hour daily METH sessions separated by 30-minute breaks. At the end of self-administration training, rats underwent tests of cue-induced METH seeking on withdrawal days 3 and 30. Twenty-four hours later, nucleus accumbens was dissected and then used to measure neuropeptide mRNA levels. Results Behavioral results show that male rats increased the number of METH infusions earlier during self-administration training and took more METH than females. Both male and female rats could be further divided into 2 phenotypes labeled high and low takers based on the degree of escalation that they exhibited during the course of the METH self-administration experiment. Both males and females exhibited incubation of METH seeking after 30 days of forced withdrawal. Females had higher basal mRNA levels of dynorphin and hypocretin/orexin receptors than males, whereas males expressed higher vasopressin mRNA levels than females under saline and METH conditions. Unexpectedly, only males showed increased expression of nucleus accumbens dynorphin after METH self-administration. Moreover, there were significant correlations between nucleus accumbens Hcrtr1, Hcrtr2, Crhr2, and Avpr1b mRNA levels and cue-induced METH seeking only in female rats. Conclusion Our results identify some behavioral and molecular differences between male and female rats that had self-administered METH. Sexual dimorphism in responses to METH exposure should be considered when developing potential therapeutic agents against METH use disorder.

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BDNF-TrkB controls cocaine-induced dendritic spines in rodent nucleus accumbens dissociated from increases in addictive behaviors

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1702441114 ◽

2017 ◽

Vol 114 (35) ◽

pp. 9469-9474 ◽

Cited By ~ 12

Author(s):

Ethan M. Anderson ◽

Anne Marie Wissman ◽

Joyce Chemplanikal ◽

Nicole Buzin ◽

Daniel Guzman ◽

...

Keyword(s):

Nucleus Accumbens ◽

Dendritic Spine ◽

Morphological Changes ◽

Dominant Negative ◽

Addictive Behaviors ◽

Spine Density ◽

Nucleus Accumbens Shell ◽

Self Administration ◽

Dendritic Spine Density ◽

Chronic Cocaine

Chronic cocaine use is associated with prominent morphological changes in nucleus accumbens shell (NACsh) neurons, including increases in dendritic spine density along with enhanced motivation for cocaine, but a functional relationship between these morphological and behavioral phenomena has not been shown. Here we show that brain-derived neurotrophic factor (BDNF) signaling through tyrosine kinase B (TrkB) receptors in NACsh neurons is necessary for cocaine-induced dendritic spine formation by using either localized TrkB knockout or viral-mediated expression of a dominant negative, kinase-dead TrkB mutant. Interestingly, augmenting wild-type TrkB expression after chronic cocaine self-administration reverses the sustained increase in dendritic spine density, an effect mediated by TrkB signaling pathways that converge on extracellular regulated kinase. Loss of TrkB function after cocaine self-administration, however, leaves spine density intact but markedly enhances the motivation for cocaine, an effect mediated by specific loss of TrkB signaling through phospholipase Cgamma1 (PLCγ1). Conversely, overexpression of PLCγ1 both reduces the motivation for cocaine and reverses dendritic spine density, suggesting a potential target for the treatment of addiction in chronic users. Together, these findings indicate that BDNF-TrkB signaling both mediates and reverses cocaine-induced increases in dendritic spine density in NACsh neurons, and these morphological changes are entirely dissociable from changes in addictive behavior.

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Dopamine receptors mediate strategy abandoning via modulation of a specific prelimbic cortex–nucleus accumbens pathway in mice

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1717106115 ◽

2018 ◽

Vol 115 (21) ◽

pp. E4890-E4899 ◽

Cited By ~ 9

Author(s):

Qiaoling Cui ◽

Qian Li ◽

Hongyan Geng ◽

Lei Chen ◽

Nancy Y. Ip ◽

...

Keyword(s):

Nucleus Accumbens ◽

Dopamine Receptors ◽

Cortical Neurons ◽

Critical Role ◽

D2 Receptor ◽

Receptor Activation ◽

Prelimbic Cortex ◽

Dopamine Depletion ◽

Dopaminergic Tone ◽

Type Receptor

The ability to abandon old strategies and adopt new ones is essential for survival in a constantly changing environment. While previous studies suggest the importance of the prefrontal cortex and some subcortical areas in the generation of strategy-switching flexibility, the fine neural circuitry and receptor mechanisms involved are not fully understood. In this study, we showed that optogenetic excitation and inhibition of the prelimbic cortex–nucleus accumbens (NAc) pathway in the mouse respectively enhances and suppresses strategy-switching ability in a cross-modal spatial-egocentric task. This ability is dependent on an intact dopaminergic tone in the NAc, as local dopamine denervation impaired the performance of the animal in the switching of tasks. In addition, based on a brain-slice preparation obtained from Drd2-EGFP BAC transgenic mice, we demonstrated direct innervation of D2 receptor-expressing medium spiny neurons (D2-MSNs) in the NAc by prelimbic cortical neurons, which is under the regulation by presynaptic dopamine receptors. While presynaptic D1-type receptor activation enhances the glutamatergic transmission from the prelimbic cortex to D2-MSNs, D2-type receptor activation suppresses this synaptic connection. Furthermore, manipulation of this pathway by optogenetic activation or administration of a D1-type agonist or a D2-type antagonist could restore impaired task-switching flexibility in mice with local NAc dopamine depletion; this restoration is consistent with the effects of knocking down the expression of specific dopamine receptors in the pathway. Our results point to a critical role of a specific prelimbic cortex–NAc subpathway in mediating strategy abandoning, allowing the switching from one strategy to another in problem solving.

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