{"title":"The mGlu2/3 agonist LY379268 reduces sucrose taking, seeking, and motivation in male and female rats.","authors":"Jeffrey William Grimm, Frances Sauter, Derek MacDougall, Emily Spaulding, Kyra Stensgaard, Mason Hardy, Kyle Griffin, Rebecca Marx","doi":"10.1097/FBP.0000000000000740","DOIUrl":null,"url":null,"abstract":"<p><strong>Objectives: </strong>The mGlu2/3 receptor agonist LY379268 reduces sucrose-seeking, but not sucrose-taking, in male rats. This study explored the generality of this effect across the sexes. In addition, the effect of the drug on motivation to receive sucrose was assessed.</p><p><strong>Methods: </strong>Adult male and female Long-Evans rats ( N = 91) were challenged with LY379268 in three experiments: (1) a fixed ratio (FR) schedule of reinforcement (taking), (2) extinction of responding previously reinforced on the FR (seeking) or (3) responding reinforced on a progressive ratio (PR) schedule of reinforcement (motivation). For each experiment, rats first responded to 10% liquid sucrose on an FR in 10 daily 2-h sessions. For the PR study, this was followed by training on a PR for 7 daily 3-h sessions. Rats were then challenged in a counterbalanced order with LY379268 (0, 1.5, 3 and 6 mg/kg; IP; 30-min pretreatment) on test days, followed by either three reacquisition days of FR (experiments 1 and 2) or PR (experiment 3) responding.</p><p><strong>Results: </strong>Female rats responded more to sucrose on the FR and PR. LY379268 reduced responding in all three experiments. LY379268 challenge to sucrose taking on the FR produced an inverted U-shaped function while extinction responding and responding for sucrose on the PR were decreased dose-dependently, with PR responding insensitive to the 1.5 mg/kg dose. There were no sex-dependent effects of the drug on sucrose-directed responding.</p><p><strong>Conclusions: </strong>The sucrose anti-taking, -seeking, and -motivation effects of LY379268 across male and female rats support further evaluation of glutamate modulation as an antiaddiction pharmacotherapy.</p>","PeriodicalId":8832,"journal":{"name":"Behavioural Pharmacology","volume":"34 6","pages":"340-349"},"PeriodicalIF":1.6000,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10527415/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Behavioural Pharmacology","FirstCategoryId":"102","ListUrlMain":"https://doi.org/10.1097/FBP.0000000000000740","RegionNum":4,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2023/7/11 0:00:00","PubModel":"Epub","JCR":"Q3","JCRName":"BEHAVIORAL SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
Objectives: The mGlu2/3 receptor agonist LY379268 reduces sucrose-seeking, but not sucrose-taking, in male rats. This study explored the generality of this effect across the sexes. In addition, the effect of the drug on motivation to receive sucrose was assessed.
Methods: Adult male and female Long-Evans rats ( N = 91) were challenged with LY379268 in three experiments: (1) a fixed ratio (FR) schedule of reinforcement (taking), (2) extinction of responding previously reinforced on the FR (seeking) or (3) responding reinforced on a progressive ratio (PR) schedule of reinforcement (motivation). For each experiment, rats first responded to 10% liquid sucrose on an FR in 10 daily 2-h sessions. For the PR study, this was followed by training on a PR for 7 daily 3-h sessions. Rats were then challenged in a counterbalanced order with LY379268 (0, 1.5, 3 and 6 mg/kg; IP; 30-min pretreatment) on test days, followed by either three reacquisition days of FR (experiments 1 and 2) or PR (experiment 3) responding.
Results: Female rats responded more to sucrose on the FR and PR. LY379268 reduced responding in all three experiments. LY379268 challenge to sucrose taking on the FR produced an inverted U-shaped function while extinction responding and responding for sucrose on the PR were decreased dose-dependently, with PR responding insensitive to the 1.5 mg/kg dose. There were no sex-dependent effects of the drug on sucrose-directed responding.
Conclusions: The sucrose anti-taking, -seeking, and -motivation effects of LY379268 across male and female rats support further evaluation of glutamate modulation as an antiaddiction pharmacotherapy.
期刊介绍:
Behavioural Pharmacology accepts original full and short research reports in diverse areas ranging from ethopharmacology to the pharmacology of schedule-controlled operant behaviour, provided that their primary focus is behavioural. Suitable topics include drug, chemical and hormonal effects on behaviour, the neurochemical mechanisms under-lying behaviour, and behavioural methods for the study of drug action. Both animal and human studies are welcome; however, studies reporting neurochemical data should have a predominantly behavioural focus, and human studies should not consist exclusively of clinical trials or case reports. Preference is given to studies that demonstrate and develop the potential of behavioural methods, and to papers reporting findings of direct relevance to clinical problems. Papers making a significant theoretical contribution are particularly welcome and, where possible and merited, space is made available for authors to explore fully the theoretical implications of their findings. Reviews of an area of the literature or at an appropriate stage in the development of an author’s own work are welcome. Commentaries in areas of current interest are also considered for publication, as are Reviews and Commentaries in areas outside behavioural pharmacology, but of importance and interest to behavioural pharmacologists. Behavioural Pharmacology publishes frequent Special Issues on current hot topics. The editors welcome correspondence about whether a paper in preparation might be suitable for inclusion in a Special Issue.