{"title":"Dual activation of 5-HT1A and μ-opioid receptors mediates dezocine's antidepressant effects in mice with comorbid pain and depression","authors":"Qian-Qian Wei , Kun-Hong Zhong , Xiao-Ke Zhang , Liangxue Zhou , Qing Zhu , Junxu Li","doi":"10.1016/j.pbb.2025.174136","DOIUrl":"10.1016/j.pbb.2025.174136","url":null,"abstract":"<div><h3>Background</h3><div>Pain-depression morbidity affects millions, but there are no effective treatments available. Dezocine is a clinically used opioid analgesic with complicated pharmacological mechanisms. Given this unique pharmacological profile and the crucial involvement of noradrenergic/serotonergic systems in the pathophysiology of depression, dezocine might be able to relieve pain-depression comorbidity. This possibility has not been tested and is the focus of this study. However, this potential has not yet been empirically validated, and investigating it constitutes the primary aim of this study.</div></div><div><h3>Methods</h3><div>Animal models of depression (Lipopolysaccharides [LPS] and chronic unpredictable mild stress models [CUMS]) were established, and two neuropathic pain models (chronic constriction injury [CCI] and spared nerve injury [SNI]) were used to establish chronic pain-induced depressive-like behaviors and the antidepressive-like effects of dezocine were then examined. Tail suspension test (TST) and force swimming test (FST) were used as behavioral readouts of antidepressant effects. For receptor mechanisms studies, 5-HT<sub>1A</sub> receptor antagonist WAY-100635, nonselective opioid receptor antagonist naltrexone [NTX]), and three selective opioid receptor antagonists (μ: CTAP; δ: naltrindole [NAL]; k: nor-binaltorphimine [nor-BNI]) were used as pretreatment to antagonize the effects of dezocine.</div></div><div><h3>Results</h3><div>Dezocine (5 and 10 mg/kg, i.p.) significantly reduced immobility time, suggesting its robust antidepressive-like effects in stand-alone depression models and in neuropathic pain-induced depression models. WAY-100635, NTX, and CTAP but not NAL or nBNI blocked the antidepressive-like effects of dezocine, suggesting the involvement of 5-HT<sub>1A</sub> and μ-opioid receptors in mediating the antidepressive-like effects of dezocine.</div></div><div><h3>Conclusion</h3><div>This study demonstrates that dezocine alleviates pain-depression comorbidity by activating both 5-HT<sub>1A</sub> and μ-opioid receptor.</div></div>","PeriodicalId":19893,"journal":{"name":"Pharmacology Biochemistry and Behavior","volume":"259 ","pages":"Article 174136"},"PeriodicalIF":2.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145715290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Larysa Bondarenko , Tetiana Karatsuba , Alla Voronina , Maksim Munko , Valentina Kovalenko , Ganna Shayakhmetova
{"title":"Peripubertal PTSD-like stress in rats induces transient behavioral but lasting metabolic and inflammatory alterations: Limited fluoxetine efficacy","authors":"Larysa Bondarenko , Tetiana Karatsuba , Alla Voronina , Maksim Munko , Valentina Kovalenko , Ganna Shayakhmetova","doi":"10.1016/j.pbb.2025.174143","DOIUrl":"10.1016/j.pbb.2025.174143","url":null,"abstract":"<div><div>Post-traumatic stress disorder (PTSD) is increasingly recognized as a systemic disorder, with neuroendocrine, metabolic, and immune alterations accompanying its behavioral symptoms. While selective serotonin reuptake inhibitors such as fluoxetine are widely used to treat PTSD, their systemic effects during critical developmental periods remain poorly understood. Using a peripubertal rat model of PTSD-like stress, we evaluated the effects of fluoxetine administered during puberty on behavior (passive avoidance), serum biochemistry, hematology, and IL-6 levels. Assessments were conducted in two phases: shortly following the end of fluoxetine treatment and in a delayed post-treatment period. PTSD-like stress enhanced aversive memory retention, an effect attenuated by fluoxetine in the short post-treatment phase but not in the delayed period. Uric acid content in serum was increased in both PTSD and PTSD+fluoxetine groups shortly post-treatment, while LDL elevation was observed only in the delayed phase. The long-term effect of fluoxetine on serum creatinine was observed. Additional hematological alterations were observed in the delayed period. Serum IL-6 levels remained persistently elevated in PTSD group across both phases, indicating sustained inflammation with no clear effect of fluoxetine. Thus, peripubertal PTSD-like stress induces behavioral and metabolic alterations that persist beyond the acute stress period. Fluoxetine partially normalized behavior but failed to prevent long-term biochemical and hematological alterations. These highlight the systemic and time-dependent consequences of peripubertal PTSD and its pharmacological treatment, underscoring the need for longitudinal monitoring of physiological outcomes alongside recovery of behavioral phenotype.</div></div>","PeriodicalId":19893,"journal":{"name":"Pharmacology Biochemistry and Behavior","volume":"259 ","pages":"Article 174143"},"PeriodicalIF":2.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145725082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alena Lemeshova , Kaya A. Patel , Alexander J. Bloom, Lindsay Golan, Haney Haidari, Aiman Limbada, Cherish Zhao, Jennifer A. Honeycutt
{"title":"A systematic review of ketamine's anxiolytic potential in rodent behavioral models of anxiety and PTSD","authors":"Alena Lemeshova , Kaya A. Patel , Alexander J. Bloom, Lindsay Golan, Haney Haidari, Aiman Limbada, Cherish Zhao, Jennifer A. Honeycutt","doi":"10.1016/j.pbb.2025.174144","DOIUrl":"10.1016/j.pbb.2025.174144","url":null,"abstract":"<div><h3>Background</h3><div>Ketamine, a nonselective NMDA-receptor antagonist, is an emerging therapeutic for treatment-resistant depression and could also be a promising treatment for anxiety and post-traumatic stress disorders. However, preclinical studies in these areas lack methodological standardization, limiting clinical translatability. This review evaluates ketamine's anxiolytic potential in rodents by examining outcomes among different animal models, dosages, and treatment timing.</div></div><div><h3>Methods & Results</h3><div>A PubMed search of studies published up to July 21, 2025, identified 562 articles assessing ketamine's effects on anxiety and PTSD in rodent models. After applying inclusion and exclusion criteria, 35 studies were analyzed. Key methodological variables, model type, dosage, and timing were summarized to assess consistency and effectiveness across studies.</div></div><div><h3>Conclusion</h3><div>Current research on ketamine's anxiolytic potential in rodents is limited by inconsistent methods and inadequate sex inclusion. Evidence suggests that administering 10 to 30 mg/kg intraperitoneally and waiting ≥24 h before behavioral testing procedures produces anxiolytic effects, in deficit models. Future studies should include female subjects and standardized designs to enhance clinical translatability and relevance.</div></div>","PeriodicalId":19893,"journal":{"name":"Pharmacology Biochemistry and Behavior","volume":"259 ","pages":"Article 174144"},"PeriodicalIF":2.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145757177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Daniel A. Palacios-Lagunas , Juan C. Hernández-Mondragón , Kjell Fuxe , Dasiel O. Borroto-Escuela , Minerva Crespo-Ramírez , Francisco Pérez-Eugenio , Miguel Pérez de la Mora
{"title":"The 3,4-methylenedioxymethamphetamine (MDMA) reduces prosocial behavior in the social preference test in male and female rats","authors":"Daniel A. Palacios-Lagunas , Juan C. Hernández-Mondragón , Kjell Fuxe , Dasiel O. Borroto-Escuela , Minerva Crespo-Ramírez , Francisco Pérez-Eugenio , Miguel Pérez de la Mora","doi":"10.1016/j.pbb.2025.174135","DOIUrl":"10.1016/j.pbb.2025.174135","url":null,"abstract":"<div><div>The promotion of prosocial behavior is a remarkable MDMA property. Such an effect is rather uncommon among other psychoactive substances and has been proposed to be of relevance for the potential therapeutic utility of MDMA. We aim to expand our knowledge of the prosocial effects of MDMA, considering sex and housing conditions as extra variables. To this end, housed individually or collectively, male and female Wistar rats were tested using the Social Preference paradigm.</div><div>Contrary to expectations, MDMA treatment reduced the prosocial behavior in male rats, irrespective of the housing conditions. Similar effects are observed in female rats, but only in those individually housed. Intriguingly, no MDMA social effects were observed on those female rats, which are collectively housed. Also interesting was the apparent existence of two subgroups of rats that responded differentially to the MDMA administration, suggesting that individual variations among rats may influence the degree of their response to the MDMA treatment. More work is needed to understand how differences across individuals are relevant to the behavioral effects of MDMA.</div></div>","PeriodicalId":19893,"journal":{"name":"Pharmacology Biochemistry and Behavior","volume":"259 ","pages":"Article 174135"},"PeriodicalIF":2.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145701244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yikai Chen , Wen Ye , Wenxin Wang , Nan Miao , Yongqiang Sha , Tao Sun
{"title":"Nicotinic acid (NA) facilitates antidepressant effects through promoting neuro-protective transcriptome in the hippocampus","authors":"Yikai Chen , Wen Ye , Wenxin Wang , Nan Miao , Yongqiang Sha , Tao Sun","doi":"10.1016/j.pbb.2025.174145","DOIUrl":"10.1016/j.pbb.2025.174145","url":null,"abstract":"<div><div>Major depressive disorder (MDD) is characterized by anhedonia and cognitive deficits. In this study, we investigated the therapeutic effects of nicotinic acid (NA), a nicotinamide adenine dinucleotide<sup>+</sup> (NAD<sup>+</sup>) precursor, in a mouse chronic restraint stress (CRS) model. Behavioral assessments revealed that NA ameliorated depressive-like behaviors, evidenced by restored sucrose preference and reduced immobility in forced swim and tail suspension tests, without affecting motor coordination in the rotarod test. Hippocampal transcriptomic analysis indicated that NA reversed stress-induced gene dysregulation, activated neuroprotective Wnt/β-catenin, cGMP–PKG, and cAMP pathways, and rescued lipid and porphyrin metabolism. In conclusion, NA likely exerts antidepressant effects by remodeling hippocampal gene networks to enhance synaptic plasticity and restore metabolic homeostasis. These findings highlight NA as a promising metabolic antidepressant and support the development of NAD<sup>+</sup> precursor–based potential therapies for mood disorders.</div></div>","PeriodicalId":19893,"journal":{"name":"Pharmacology Biochemistry and Behavior","volume":"259 ","pages":"Article 174145"},"PeriodicalIF":2.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145878801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Agata Siwek , Monika Marcinkowska , Barbara Mordyl , Monika Głuch-Lutwin , Małgorzata Wolak , Magdalena Jastrzębska-Więsek , Natalia Wilczyńska-Zawal , Elżbieta Wyska , Katarzyna Szafrańska , Anna Wesołowska , Marcin Kołaczkowski
{"title":"Simultaneous modulation of 5-HT6 and SERT by MM394: a dual-target ligand providing neuroprotection against amyloid-β toxicity, memory preservation, and alleviation of BPSD symptoms","authors":"Agata Siwek , Monika Marcinkowska , Barbara Mordyl , Monika Głuch-Lutwin , Małgorzata Wolak , Magdalena Jastrzębska-Więsek , Natalia Wilczyńska-Zawal , Elżbieta Wyska , Katarzyna Szafrańska , Anna Wesołowska , Marcin Kołaczkowski","doi":"10.1016/j.pbb.2025.174128","DOIUrl":"10.1016/j.pbb.2025.174128","url":null,"abstract":"<div><div>In addition to cognitive decline, 90 % of dementia patients experience behavioral and psychological symptoms of dementia, for which no safe and effective pharmacotherapy currently exists. Our study aimed to determine the therapeutic potential of the new dual 5-HT<sub>6</sub>/SERT-acting ligand MM394 in the context of pro-cognitive and neuroprotective properties, as well as its effects on behavioral symptoms and mood disorders in patients diagnosed with Alzheimer's disease. We performed <em>in vitro</em> experiments to examine the neuroprotective and antioxidant properties of MM394, as well as <em>in vivo</em> studies on male rats to evaluate its pharmacokinetics and potential in behavioral modulation of memory and mood. Following this, we attempted to determine the molecular mechanism of action of the dual 5-HT<sub>6</sub>/SERT targeting compound in <em>ex vivo</em> experiments using rats' hippocampus and prefrontal cortex. The results of our study in the HT-22 cell line support the potential of MM394 to target excitotoxicity and oxidative stress, which play a key role in neurodegeneration. Furthermore, the compound exhibits antidepressant-like activity in the forced swim test and counteracts the memory impairments caused by MK-801 in the novel object recognition assessment in rats. <em>Ex vivo</em> findings demonstrate that MM394 modulates mTOR and ERK1/2 phosphorylation in the studied brain areas and increases the level of BDNF in the hippocampus when co-administered with MK-801 in the novel object recognition test. As a result of these findings, MM394 may be useful as a therapeutic for BPSD, which should be further explored.</div></div>","PeriodicalId":19893,"journal":{"name":"Pharmacology Biochemistry and Behavior","volume":"258 ","pages":"Article 174128"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145506304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alexa R. Soares , Caroline Fai , Yann S. Mineur , Marina R. Picciotto
{"title":"Noradrenergic inputs to the basolateral amygdala have bidirectional effects on coping behavior and neuronal activity in mice","authors":"Alexa R. Soares , Caroline Fai , Yann S. Mineur , Marina R. Picciotto","doi":"10.1016/j.pbb.2025.174130","DOIUrl":"10.1016/j.pbb.2025.174130","url":null,"abstract":"<div><div>Norepinephrine (NE) signaling is disrupted in stress disorders, with insufficient NE signaling implicated in major depressive disorder and hyperactive NE signaling associated with post-traumatic stress disorder, suggesting that adequate mood regulation requires optimal NE levels. The basolateral amygdala (BLA) is a hub for stress processing and receives dense noradrenergic innervation from the locus coeruleus (LC), the primary noradrenergic nucleus in the brain. The relationship between LC activity and cognitive/behavioral function during fear conditioning has been described as an inverted U, in which moderate LC activity, and subsequent NE release, is required for adaptive coping to threats, while hyperactive LC-NE signaling drives maladaptive behavioral responses. We used fiber photometry to measure NE signaling in the mouse BLA during acute behavioral responses to escapable and inescapable stressors, and then used an optogenetic approach to stimulate the noradrenergic terminals in the BLA at different frequencies to evaluate effects on coping behavior and cFos expression in the LC-BLA circuit. We found that low-frequency stimulation of the circuit inhibited both passive coping and BLA neuronal activity, while high-frequency stimulation had the opposite effect; the behavioral effects were not mediated by sex, but the cFos effects were specific to males. This study represents an expansion of the inverted U framework to encompass LC-BLA signaling driving acute behavioral responses to stress.</div></div>","PeriodicalId":19893,"journal":{"name":"Pharmacology Biochemistry and Behavior","volume":"258 ","pages":"Article 174130"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145526833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yonca Cam , Carlos A. Sardina , Sanya K. Suri , Elizabeth C. Pickering , Felicia M. Padilla , Matthew J. Will
{"title":"Intra-accumbens melanin-concentrating hormone (MCH) receptor-1 antagonism on opioid-driven sucrose consumption in male and female rats","authors":"Yonca Cam , Carlos A. Sardina , Sanya K. Suri , Elizabeth C. Pickering , Felicia M. Padilla , Matthew J. Will","doi":"10.1016/j.pbb.2025.174134","DOIUrl":"10.1016/j.pbb.2025.174134","url":null,"abstract":"<div><div>Melanin-concentrating hormone (MCH) system within the nucleus accumbens (Acb) has been shown to regulate feeding behavior; however, the interaction between MCH and opioid-driven hedonic eating remains unclear. This study investigated the effects of intra-Acb administration of the MCHR1 antagonist SNAP-94847 on opioid-driven sucrose pellet intake in male and female rats. Subjects received MCHR1 antagonist (N-(3-{1-[4-(3,4-difluoro-phenoxy)-benzyl]-piperdin-4-yl}-4-methyl-phenyl)-isobutyramide (SNAP-94847; 0 μg, 1.5 μg, and 15 μg/0.5 μl/side) immediately prior to intra-Acb administration of the μ-opioid receptor agonist, D-Ala2, NMe-Phe4, Glyol5-enkephalin (DAMGO; 0 μg and 0.025 μg/0.5 μl/side) before completing free-feeding tests. Results showed that DAMGO significantly increased sucrose pellet intake in both sexes, while SNAP-94847 alone had no effect, nor did it block the DAMGO-induced increase in either males or females. This finding suggests that MCHR1 within the Acb does not play a significant role in low-effort palatability-driven motivation for food consumption, contrasting with its role in effort-based motivation tasks.</div></div>","PeriodicalId":19893,"journal":{"name":"Pharmacology Biochemistry and Behavior","volume":"258 ","pages":"Article 174134"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145621255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dual orexin receptor antagonists in insomnia: Toward a new therapeutic paradigm","authors":"Shigeyuki Chaki , Yumiko Imadera","doi":"10.1016/j.pbb.2025.174117","DOIUrl":"10.1016/j.pbb.2025.174117","url":null,"abstract":"<div><div>Although three dual orexin receptor antagonists (DORAs), suvorexant, lemborexant, and daridorexant, are currently available and widely used to treat insomnia, the differences in their elimination half-lives are not sufficient. As a result, clinicians have limited ability to tailor therapy to individual sleep complaints. The emergence of vornorexant, with a notably short half-life comparable to that of zolpidem, may substantially expand the clinical utility of DORAs. This broader spectrum of pharmacokinetic profiles enables more individualized treatment strategies that align with patients' specific sleep complaints. This approach, in turn, potentially reshapes the therapeutic paradigm of insomnia management. However, several challenges remain to be addressed in order to fully realize the clinical potential of DORAs. This review identifies four key challenges requiring resolution to advance their optimal use in clinical practice.</div></div>","PeriodicalId":19893,"journal":{"name":"Pharmacology Biochemistry and Behavior","volume":"258 ","pages":"Article 174117"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145370357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michael A. Taffe , Tyra R. Coons , Tess A. Doran , Yanabel Grant , Sophia A. Vandewater
{"title":"6-Methyl nicotine and nicotine have similar thermoregulatory and reinforcing effects in middle aged female rats with a history of nicotine vapor self-administration","authors":"Michael A. Taffe , Tyra R. Coons , Tess A. Doran , Yanabel Grant , Sophia A. Vandewater","doi":"10.1016/j.pbb.2025.174132","DOIUrl":"10.1016/j.pbb.2025.174132","url":null,"abstract":"<div><h3>Rationale</h3><div>The nicotine analog 6-methyl nicotine (6-MN) has recently appeared in non-tobacco nicotine delivery products, including oral pouches and e-cigarette liquids, in an apparent ploy to evade regulation of nicotine by the United States Food and Drug Administration or other public health agencies. Unfortunately, only minimal scientific information on the effects of 6-MN is available.</div></div><div><h3>Objective</h3><div>To determine the extent to which 6-MN produces nicotine-like effects on body temperature, wheel activity and nociception in laboratory rodents.</div></div><div><h3>Methods</h3><div>Middle-aged (starting at Post Natal Day 425) female Wistar rats were evaluated for rectal temperature, voluntary wheel activity, and nociceptive responses (warm water tail-withdrawal) to subcutaneous injection of nicotine (0.0, 0.8 mg/kg) or 6-methyl nicotine (6-MN; 0.0, 0.4, 0.8 mg/kg). Temperature and nociceptive responses to vapor inhalation of 6-MN [0–30 mg/mL in the propylene glycol (PG) vehicle] were assessed. Finally, the self-administration of 6-MN vapor was compared with nicotine vapor self-administration.</div></div><div><h3>Results</h3><div>6-MN decreased rectal temperature, suppressed wheel activity and induced modest nociceptive effects. The magnitude of the effect of 0.8 mg/kg 6-MN and 0.8 mg/kg nicotine were similar across all three assays. Vapor self-administration of 6-MN and nicotine was likewise comparable at a 10 mg/mL concentration.</div></div><div><h3>Conclusion</h3><div>6-MN administered by injection or by vapor inhalation produces behavioral and physiological effects that are very similar to those produced by nicotine in rats. It is therefore likely that detrimental health effects of 6-MN will be quite similar to those established for nicotine.</div></div>","PeriodicalId":19893,"journal":{"name":"Pharmacology Biochemistry and Behavior","volume":"258 ","pages":"Article 174132"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145533854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}