Mackenzie M Spicer, Matthew A Weber, Zili Luo, Jianqi Yang, Nandakumar S Narayanan, Rory A Fisher
{"title":"Regulator of G protein signaling 6 (RGS6) in dopamine neurons promotes EtOH seeking, behavioral reward, and susceptibility to relapse.","authors":"Mackenzie M Spicer, Matthew A Weber, Zili Luo, Jianqi Yang, Nandakumar S Narayanan, Rory A Fisher","doi":"10.1007/s00213-024-06631-8","DOIUrl":null,"url":null,"abstract":"<p><p>Mesolimbic dopamine (DA) transmission is believed to play a critical role in mediating reward responses to drugs of abuse, including alcohol (EtOH). The neurobiological mechanisms underlying EtOH-seeking behavior and dependence are not fully understood, and abstinence remains the only effective way to prevent alcohol use disorders (AUDs). Here, we developed novel RGS6<sup>fl/fl</sup>; DAT-iCreER mice to determine the role of RGS6 in DA neurons on EtOH consumption, reward, and relapse behaviors. We found that RGS6 is expressed in DA neurons in both human and mouse ventral tegmental area (VTA), and that RGS6 loss in mice upregulates DA transporter (DAT) expression in VTA DA neuron synaptic terminals. Remarkably, loss of RGS6 in DA neurons significantly reduced EtOH consumption, preference, and reward in a manner indistinguishable from that seen in RGS6<sup>-/-</sup> mice. Strikingly, RGS6 loss from DA neurons before or after EtOH behavioral reward is established significantly reduced (~ 50%) re-instatement of reward following extinguishment, demonstrating distinct roles of RGS6 in promoting reward and relapse susceptibility to EtOH. These studies identify DA neurons as the locus of RGS6 action in promoting EtOH consumption, preference, reward, and relapse. RGS6 is unique among R7 RGS proteins in promoting rather than suppressing behavioral responses to drugs of abuse and to modulate EtOH behavioral reward. This is a result of RGS6's pre-synaptic actions that we hypothesize promote VTA DA transmission by suppressing GPCR-Gα<sub>i/o</sub>-DAT signaling in VTA DA neurons. These studies identify RGS6 as a potential therapeutic target for behavioral reward and relapse to EtOH.</p>","PeriodicalId":20783,"journal":{"name":"Psychopharmacology","volume":null,"pages":null},"PeriodicalIF":3.5000,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11518640/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Psychopharmacology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1007/s00213-024-06631-8","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/6/10 0:00:00","PubModel":"Epub","JCR":"Q2","JCRName":"NEUROSCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
Mesolimbic dopamine (DA) transmission is believed to play a critical role in mediating reward responses to drugs of abuse, including alcohol (EtOH). The neurobiological mechanisms underlying EtOH-seeking behavior and dependence are not fully understood, and abstinence remains the only effective way to prevent alcohol use disorders (AUDs). Here, we developed novel RGS6fl/fl; DAT-iCreER mice to determine the role of RGS6 in DA neurons on EtOH consumption, reward, and relapse behaviors. We found that RGS6 is expressed in DA neurons in both human and mouse ventral tegmental area (VTA), and that RGS6 loss in mice upregulates DA transporter (DAT) expression in VTA DA neuron synaptic terminals. Remarkably, loss of RGS6 in DA neurons significantly reduced EtOH consumption, preference, and reward in a manner indistinguishable from that seen in RGS6-/- mice. Strikingly, RGS6 loss from DA neurons before or after EtOH behavioral reward is established significantly reduced (~ 50%) re-instatement of reward following extinguishment, demonstrating distinct roles of RGS6 in promoting reward and relapse susceptibility to EtOH. These studies identify DA neurons as the locus of RGS6 action in promoting EtOH consumption, preference, reward, and relapse. RGS6 is unique among R7 RGS proteins in promoting rather than suppressing behavioral responses to drugs of abuse and to modulate EtOH behavioral reward. This is a result of RGS6's pre-synaptic actions that we hypothesize promote VTA DA transmission by suppressing GPCR-Gαi/o-DAT signaling in VTA DA neurons. These studies identify RGS6 as a potential therapeutic target for behavioral reward and relapse to EtOH.
期刊介绍:
Official Journal of the European Behavioural Pharmacology Society (EBPS)
Psychopharmacology is an international journal that covers the broad topic of elucidating mechanisms by which drugs affect behavior. The scope of the journal encompasses the following fields:
Human Psychopharmacology: Experimental
This section includes manuscripts describing the effects of drugs on mood, behavior, cognition and physiology in humans. The journal encourages submissions that involve brain imaging, genetics, neuroendocrinology, and developmental topics. Usually manuscripts in this section describe studies conducted under controlled conditions, but occasionally descriptive or observational studies are also considered.
Human Psychopharmacology: Clinical and Translational
This section comprises studies addressing the broad intersection of drugs and psychiatric illness. This includes not only clinical trials and studies of drug usage and metabolism, drug surveillance, and pharmacoepidemiology, but also work utilizing the entire range of clinically relevant methodologies, including neuroimaging, pharmacogenetics, cognitive science, biomarkers, and others. Work directed toward the translation of preclinical to clinical knowledge is especially encouraged. The key feature of submissions to this section is that they involve a focus on clinical aspects.
Preclinical psychopharmacology: Behavioral and Neural
This section considers reports on the effects of compounds with defined chemical structures on any aspect of behavior, in particular when correlated with neurochemical effects, in species other than humans. Manuscripts containing neuroscientific techniques in combination with behavior are welcome. We encourage reports of studies that provide insight into the mechanisms of drug action, at the behavioral and molecular levels.
Preclinical Psychopharmacology: Translational
This section considers manuscripts that enhance the confidence in a central mechanism that could be of therapeutic value for psychiatric or neurological patients, using disease-relevant preclinical models and tests, or that report on preclinical manipulations and challenges that have the potential to be translated to the clinic. Studies aiming at the refinement of preclinical models based upon clinical findings (back-translation) will also be considered. The journal particularly encourages submissions that integrate measures of target tissue exposure, activity on the molecular target and/or modulation of the targeted biochemical pathways.
Preclinical Psychopharmacology: Molecular, Genetic and Epigenetic
This section focuses on the molecular and cellular actions of neuropharmacological agents / drugs, and the identification / validation of drug targets affecting the CNS in health and disease. We particularly encourage studies that provide insight into the mechanisms of drug action at the molecular level. Manuscripts containing evidence for genetic or epigenetic effects on neurochemistry or behavior are welcome.