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Hung CC, Ko YC, Chung CM. Association between Single Nucleotide Polymorphisms in Monoamine Oxidase and the Severity of Addiction to Betel Quid. Curr Issues Mol Biol 2024; 46:1010-1019. [PMID: 38392182 PMCID: PMC10887354 DOI: 10.3390/cimb46020064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 01/19/2024] [Accepted: 01/22/2024] [Indexed: 02/24/2024] Open
Abstract
Betel quid (BQ) is the fourth most popular psychoactive substance in the world, and BQ use disorder (BUD) is prevalent in Asian countries. Although the mechanisms underlying BUD remain unclear, studies have reported influences from monoamine oxidase inhibitor. We enrolled 50 patients with BUD and assessed their BQ consumption habits, emotional conditions, and the clinical severity of addiction-assessed using the Diagnostic and Statistical Manual of Mental Disorders [Fifth Edition] (DSM-5) criteria, Substance Use Severity Rating Scale, and Yale-Brown Obsessive Compulsive Disorder Rating Scale for BQ. Patients were categorized into the severe group when showing six or more symptoms defined by DSM-5. A genome-wide association study was conducted for single nucleotide polymorphisms in BRCA1, COL9A1, NOTCH1, HSPA13, FAT1, and MAOA by using patients' blood samples. More severe BUD symptoms were associated with younger age of using BQ and poor oral hygiene and with severe craving for and more anxiety toward BQ use. The MAOA rs5953210 polymorphism was significantly associated with severe BUD (odds ratio, 6.43; 95% confidence interval, 5.12-7.74; p < 0.01) and might contribute to BQ-associated cancer risk. Further studies are required to investigate the addictive properties of BQ and the development of novel diagnostic tools and pharmacotherapeutic alternatives to BUD treatment.
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Affiliation(s)
- Chung-Chieh Hung
- School of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan
- Department of Psychiatry, Chung Shan Medical University Hospital, Taichung 40201, Taiwan
| | - Ying-Chin Ko
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung 40447, Taiwan
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei 106216, Taiwan
| | - Chia-Min Chung
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung 40402, Taiwan
- Department of Psychiatry and Center for Addiction and Mental Health, China Medical University Hospital, Taichung 404327, Taiwan
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Sved AF, Weeks JJ, Grace AA, Smith TT, Donny EC. Monoamine oxidase inhibition in cigarette smokers: From preclinical studies to tobacco product regulation. Front Neurosci 2022; 16:886496. [PMID: 36051642 PMCID: PMC9424897 DOI: 10.3389/fnins.2022.886496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 07/21/2022] [Indexed: 11/13/2022] Open
Abstract
Monoamine oxidase (MAO) activity is reduced in cigarette smokers and this may promote the reinforcing actions of nicotine, thereby enhancing the addictive properties of cigarettes. At present, it is unclear how cigarette smoking leads to MAO inhibition, but preclinical studies in rodents show that MAO inhibition increases nicotine self-administration, especially at low doses of nicotine. This effect of MAO inhibition develops slowly, likely due to plasticity of brain monoamine systems; studies relying on acute MAO inhibition are unlikely to replicate what happens with smoking. Given that MAO inhibition may reduce the threshold level at which nicotine becomes reinforcing, it is important to consider this in the context of very low nicotine content (VLNC) cigarettes and potential tobacco product regulation. It is also important to consider how this interaction between MAO inhibition and the reinforcing actions of nicotine may be modified in populations that are particularly vulnerable to nicotine dependence. In the context of these issues, we show that the MAO-inhibiting action of cigarette smoke extract (CSE) is similar in VLNC cigarettes and cigarettes with a standard nicotine content. In addition, we present evidence that in a rodent model of schizophrenia the effect of MAO inhibition to enhance nicotine self-administration is absent, and speculate how this may relate to brain serotonin systems. These issues are relevant to the MAO-inhibiting effect of cigarette smoking and its implications to tobacco product regulation.
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Affiliation(s)
- Alan F. Sved
- Departments of Neuroscience, Psychiatry and Psychology, University of Pittsburgh, Pittsburgh, PA, United States
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States
- *Correspondence: Alan F. Sved,
| | - Jillian J. Weeks
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States
| | - Anthony A. Grace
- Departments of Neuroscience, Psychiatry and Psychology, University of Pittsburgh, Pittsburgh, PA, United States
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States
| | - Tracy T. Smith
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States
| | - Eric C. Donny
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC, United States
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Ding Z, Li X, Chen H, Hou H, Hu Q. Harmane Potentiates Nicotine Reinforcement Through MAO-A Inhibition at the Dose Related to Cigarette Smoking. Front Mol Neurosci 2022; 15:925272. [PMID: 35832393 PMCID: PMC9271706 DOI: 10.3389/fnmol.2022.925272] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 06/07/2022] [Indexed: 11/14/2022] Open
Abstract
Nicotine is the primary addictive component in cigarette smoke, and dopamine release induced by nicotine is considered a significant cause of persistent smoking and nicotine dependence. However, the effects of nicotine replacement therapy on smoking cessation were less effective than expected, suggesting that other non-nicotine constituents may potentiate the reinforcing effects of nicotine. Harmane is a potent, selective monoamine oxidase A (MAO-A) inhibitor found in cigarette smoke, but showed no effect on nicotine self-administration in previous studies, possibly due to the surprisingly high doses used. In the present study, we found that harmane potentiated nicotine self-administration on the fixed ration schedule at the dose related to human cigarette smoking by the synergistic effects in up-regulating genes in addiction-related pathways, and the effect was reduced at doses 10 times higher or lower than the smoking-related dose. The smoking-related dose of harmane also enhanced the increase of locomotor activity induced by nicotine, accompanied by increased dopamine basal level and dopamine release in the nucleus accumbens through MAO-A inhibition. Our findings provided new evidence for the important role of non-nicotine ingredients of tobacco products in smoking addiction.
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Affiliation(s)
- Zheng Ding
- China National Tobacco Quality Supervision & Test Center, Zhengzhou, China,Key Laboratory of Tobacco Biological Effects, Zhengzhou, China,Joint Laboratory of Translational Neurobiology, Zhengzhou, China
| | - Xiangyu Li
- China National Tobacco Quality Supervision & Test Center, Zhengzhou, China,Key Laboratory of Tobacco Biological Effects, Zhengzhou, China,Joint Laboratory of Translational Neurobiology, Zhengzhou, China
| | - Huan Chen
- China National Tobacco Quality Supervision & Test Center, Zhengzhou, China,Key Laboratory of Tobacco Biological Effects, Zhengzhou, China,Joint Laboratory of Translational Neurobiology, Zhengzhou, China
| | - Hongwei Hou
- China National Tobacco Quality Supervision & Test Center, Zhengzhou, China,Key Laboratory of Tobacco Biological Effects, Zhengzhou, China,Joint Laboratory of Translational Neurobiology, Zhengzhou, China,*Correspondence: Hongwei Hou,
| | - Qingyuan Hu
- China National Tobacco Quality Supervision & Test Center, Zhengzhou, China,Key Laboratory of Tobacco Biological Effects, Zhengzhou, China,Joint Laboratory of Translational Neurobiology, Zhengzhou, China,Qingyuan Hu,
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Hong SW, Teesdale-Spittle P, Page R, Ellenbroek B, Truman P. Biologically Active Compounds Present in Tobacco Smoke: Potential Interactions Between Smoking and Mental Health. Front Neurosci 2022; 16:885489. [PMID: 35557609 PMCID: PMC9087043 DOI: 10.3389/fnins.2022.885489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 03/28/2022] [Indexed: 12/01/2022] Open
Abstract
Tobacco dependence remains one of the major preventable causes of premature morbidity and mortality worldwide. There are well over 8,000 compounds present in tobacco and tobacco smoke, but we do not know what effect, if any, many of them have on smokers. Major interest has been on nicotine, as well as on toxic and carcinogenic effects and several major and minor components of tobacco smoke responsible for the negative health effects of smoking have been elucidated. Smokers themselves report a variety of positive effects from smoking, including effects on depression, anxiety and mental acuity. Smoking has also been shown to have protective effects in Parkinson’s Disease. Are the subjective reports of a positive effect of smoking due to nicotine, of some other components of tobacco smoke, or are they a manifestation of the relief from nicotine withdrawal symptoms that smoking provides? This mini-review summarises what is currently known about the components of tobacco smoke with potential to have positive effects on smokers.
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Affiliation(s)
- Sa Weon Hong
- School of Health Sciences, Massey University, Wellington, New Zealand
| | - Paul Teesdale-Spittle
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Rachel Page
- School of Health Sciences, Massey University, Wellington, New Zealand
| | - Bart Ellenbroek
- Department of Psychology, Victoria University of Wellington, Wellington, New Zealand
| | - Penelope Truman
- School of Health Sciences, Massey University, Wellington, New Zealand
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Harris AC, Muelken P, LeSage MG. β-Carbolines found in cigarette smoke elevate intracranial self-stimulation thresholds in rats. Pharmacol Biochem Behav 2020; 198:173041. [PMID: 32926882 PMCID: PMC7554228 DOI: 10.1016/j.pbb.2020.173041] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 09/04/2020] [Accepted: 09/07/2020] [Indexed: 12/25/2022]
Abstract
Identifying novel constituents that contribute to tobacco addiction is essential for developing more effective treatments and informing FDA regulation of tobacco products. While preclinical data indicate that monoamine oxidase (MAO) inhibitors can have abuse liability or potentiate the addiction-related effects of nicotine, most of these studies have used clinical MAO inhibitors (e.g., tranylcypromine) that are not present in cigarette smoke. The primary goal of this study was to evaluate the abuse potential of the β-carbolines harmane, norharmane, and harmine - MAO inhibitors that are found in cigarette smoke - in an intracranial self-simulation (ICSS) model in rats. A secondary goal was to evaluate the ability of norharmane to influence nicotine's acute effects on ICSS. None of the β-carbolines lowered ICSS thresholds at any dose studied when administered alone, suggesting a lack of abuse liability. Rather, all three β-carbolines produced dose-dependent elevations in ICSS thresholds, indicating aversive/anhedonic effects. Harmane and harmine also elevated ICSS response latencies, suggesting a disruption of motor function, albeit with reduced potency compared to their ICSS threshold-elevating effects. Norharmane (2.5 mg/kg) modestly attenuated the effects of nicotine on ICSS thresholds. Our findings indicate that these β-carbolines produced only aversive/anhedonic effects in an ICSS model when administered alone, and that norharmane unexpectedly attenuated nicotines acute effects on ICSS. Future work evaluating the addiction-related effects of nicotine combined with these and other MAO inhibitors present in smoke may be useful for understanding the role of MAO inhibition in tobacco addiction and informing FDA tobacco regulation.
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Affiliation(s)
- Andrew C Harris
- Hennepin Healthcare Research Institute, Minneapolis, MN, United States of America; Department of Medicine, University of Minnesota Medical School, Minneapolis, MN, United States of America; Department of Psychology, University of Minnesota, Minneapolis, MN, United States of America.
| | - Peter Muelken
- Hennepin Healthcare Research Institute, Minneapolis, MN, United States of America
| | - Mark G LeSage
- Hennepin Healthcare Research Institute, Minneapolis, MN, United States of America; Department of Medicine, University of Minnesota Medical School, Minneapolis, MN, United States of America; Department of Psychology, University of Minnesota, Minneapolis, MN, United States of America
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6
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The effect of nicotine and nicotine+monoamine oxidase inhibitor on the value of alcohol. Behav Pharmacol 2018; 30:363-369. [PMID: 30272586 DOI: 10.1097/fbp.0000000000000438] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Alcohol is the most commonly abused drug in the USA and many people suffer from alcohol use disorder. Many factors are associated with alcohol use disorder, but the causal role of comorbid nicotine use has not been extensively considered. Nicotine has reward-enhancing properties and may increase the value of alcohol. Monoamine oxidase inhibition increases nicotine self-administration and may increase the reward-enhancing effects of nicotine. We assessed the effect of nicotine and nicotine in combination with a commonly used monoamine oxidase inhibitor (tranylcypromine) on the value of alcohol using a progressive ratio schedule of reinforcement in rats. Nicotine administration increased the breakpoint for alcohol, but nicotine in combination with tranylcypromine decreased the breakpoint for alcohol. The current study adds to previous research showing that nicotine increases the value of alcohol. This finding has important implications for the etiology of addiction because of the comorbidity of smoking with many drugs of abuse. The finding that nicotine in combination with tranylcypromine reduces the value of alcohol warrants further investigation.
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Truman P, Grounds P, Brennan KA. Monoamine oxidase inhibitory activity in tobacco particulate matter: Are harman and norharman the only physiologically relevant inhibitors? Neurotoxicology 2017; 59:22-26. [PMID: 28057462 DOI: 10.1016/j.neuro.2016.12.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 12/14/2016] [Accepted: 12/31/2016] [Indexed: 10/20/2022]
Abstract
Monoamine oxidase inhibition is significant in smokers, but it is still unclear how the inhibition that is seen in the brains and bodies of smokers is brought about. Our aim was to test the contribution of the harman and norharman in tobacco smoke to MAO-A inhibition from tobacco smoke preparations, as part of a re-examination of harman and norharman as the cause of the inhibition of MAO-A inhibition in the brain. Tobacco smoke particulate matter and cigarette smoke particulate matter were prepared and the amounts of harman and norharman measured. The results were compared with the total monoamine oxidase-A inhibitory activity. At a nicotine concentration of 0.6μM (a "physiological" concentration in blood) the total monoamine oxidase-A inhibitory activity measured in these samples was sufficient to inhibit the enzyme by approximately 10%. Of this inhibitory activity, only a small proportion of the total was found to be due to harman and norharman. These results show that harman and norharman provide only a moderate contribution to the total monoamine oxidase-A inhibitory activity of tobacco smoke, perhaps under 10%. This suggests that other inhibitors (either known or unknown) may be more significant contributors to total inhibitory activity than has yet been established, and deserve closer examination.
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Affiliation(s)
- Penelope Truman
- Institute of Environmental Science and Research Ltd, Porirua, New Zealand; Massey University, Wellington, New Zealand.
| | - Peter Grounds
- Institute of Environmental Science and Research Ltd, Christchurch, New Zealand
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Smith TT, Rupprecht LE, Cwalina SN, Onimus MJ, Murphy SE, Donny EC, Sved AF. Effects of Monoamine Oxidase Inhibition on the Reinforcing Properties of Low-Dose Nicotine. Neuropsychopharmacology 2016; 41:2335-43. [PMID: 26955970 PMCID: PMC4946064 DOI: 10.1038/npp.2016.36] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 02/15/2016] [Accepted: 02/29/2016] [Indexed: 12/29/2022]
Abstract
The Food and Drug Administration (FDA) has the authority to regulate cigarette smoke constituents, and a reduction in nicotine content might benefit public health by reducing the prevalence of smoking. Research suggests that cigarette smoke constituents that inhibit monoamine oxidase (MAO) may increase the reinforcing value of low doses of nicotine. The aim of the present experiments was to further characterize the impact of MAO inhibition on the primary reinforcing and reinforcement enhancing effects of nicotine in rats. In a series of experiments, rats responded for intravenous nicotine infusions or a moderately-reinforcing visual stimulus in daily 1-h sessions. Rats received pre-session injections of known MAO inhibitors. The results show that (1) tranylcypromine (TCP), a known MAO inhibitor, increases sensitivity to the primary reinforcing effects of nicotine, shifting the dose-response curve for nicotine to the left, (2) inhibition of MAO-A, but not MAO-B, increases low-dose nicotine self-administration, (3) partial MAO-A inhibition, to the degree observed in chronic cigarette smokers, also increases low-dose nicotine self-administration, and (4) TCP decreases the threshold nicotine dose required for reinforcement enhancement. The results of the present experiments suggest cigarette smoke constituents that inhibit MAO-A, in the range seen in chronic smokers, are likely to increase the primary reinforcing and reinforcement enhancing effects of low doses of nicotine. If the FDA reduces the nicotine content of cigarettes, then variability in constituents that inhibit MAO-A could impact smoking.
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Affiliation(s)
- Tracy T Smith
- Department of Psychology, University of Pittsburgh, Pittsburgh, PA, USA,Department of Psychology, University of Pittsburgh, 4120 Sennott Square, 210 S. Bouquet Street, Pittsburgh, PA 15260, USA, Tel: +1 412 624 8525, Fax: +1 412 624 4428, E-mail:
| | - Laura E Rupprecht
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
| | | | - Matthew J Onimus
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
| | - Sharon E Murphy
- Department of Biological Sciences, University of Minnesota, Minneapolis, MN, USA
| | - Eric C Donny
- Department of Psychology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Alan F Sved
- Department of Psychology, University of Pittsburgh, Pittsburgh, PA, USA,Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
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Smith TT, Schaff MB, Rupprecht LE, Schassburger RL, Buffalari DM, Murphy SE, Sved AF, Donny EC. Effects of MAO inhibition and a combination of minor alkaloids, β-carbolines, and acetaldehyde on nicotine self-administration in adult male rats. Drug Alcohol Depend 2015; 155:243-52. [PMID: 26257022 PMCID: PMC4581969 DOI: 10.1016/j.drugalcdep.2015.07.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 07/02/2015] [Accepted: 07/02/2015] [Indexed: 12/30/2022]
Abstract
INTRODUCTION Although nicotine is the primary reinforcing constituent in cigarettes, there is evidence that other constituents in cigarette smoke may interact with nicotine to reinforce smoking behavior. METHODS The present experiments investigated whether a novel combination of these cigarette smoke constituents would increase nicotine self-administration in adult male rats. The constituents included five minor alkaloids (anabasine, nornicotine, cotinine, myosmine, and anatabine), two β-carbolines (harman and norharman), and acetaldehyde. All doses were indexed to be proportional to concentrations in cigarette smoke given a standard dose of nicotine used in rodent self-administration, or ten times higher than this standard. To model MAO inhibition seen in chronic smokers, some groups received separate injections of tranylcypromine prior to each self-administration session. RESULTS Tranylcypromine increased low-dose nicotine self-administration independent of other smoke constituents, which had no effect on self-administration behavior. The effect of tranylcypromine was confirmed across a large range of reinforcement schedules. The effect of tranylcypromine on low-dose nicotine self-administration was observed regardless of whether the injection was delivered 1-h or 23-h prior to the self-administration session, consistent with the interpretation that MAO inhibition was responsible for the increase in self-administration, instead of acute off-target effects. CONCLUSIONS These data suggest that this cocktail of constituents does not significantly alter the primary reinforcing effects of nicotine, but constituents that inhibit MAO may increase the primary reinforcing effects of nicotine, especially at low doses.
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Arnold MM, Loughlin SE, Belluzzi JD, Leslie FM. Reinforcing and neural activating effects of norharmane, a non-nicotine tobacco constituent, alone and in combination with nicotine. Neuropharmacology 2014; 85:293-304. [DOI: 10.1016/j.neuropharm.2014.05.035] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 05/14/2014] [Accepted: 05/23/2014] [Indexed: 10/25/2022]
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Lotfipour S, Arnold MM, Hogenkamp DJ, Gee KW, Belluzzi JD, Leslie FM. The monoamine oxidase (MAO) inhibitor tranylcypromine enhances nicotine self-administration in rats through a mechanism independent of MAO inhibition. Neuropharmacology 2011; 61:95-104. [PMID: 21419142 PMCID: PMC3105177 DOI: 10.1016/j.neuropharm.2011.03.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Revised: 03/05/2011] [Accepted: 03/09/2011] [Indexed: 11/16/2022]
Abstract
Our current study aims to evaluate the mechanisms of tranylcypromine (TCP)-mediated enhancement of nicotine self-administration. We replicated our previous findings which demonstrate that 1 h pretreatment with TCP (3 mg/kg, i.p.) enhances nicotine self-administration (7.5 μg/kg/inj, i.v.) when compared with vehicle-treated rodents. We tested whether TCP-mediated enhancement of nicotine self-administration was due to MAO inhibition or off-target effects by (i) extending the TCP pretreatment time from 1 to 20 h, and (ii) evaluating the role of the individual TCP stereoisomers in nicotine self-administration studies. While 20 h and (-)TCP pretreatment induced significant inhibition of MAO (60-90%), animals found nicotine only weakly reinforcing. Furthermore, while both (+) and (±)TCP treatment induced nearly 100% MAO inhibition, (+)TCP pretreated animals took longer to acquire nicotine self-administration compared to (±)TCP pretreated animals. Stable nicotine self-administration in (+)TCP pretreated animals was influenced by nicotinic receptor activation but not nicotine-paired cues. The opposite was found in (±)TCP pretreated animals. Treatment with (-) or (±)TCP increased dopamine and serotonin overflow, while the (+) and (±)TCP treatment enhanced monoamine overflow subsequent to nicotine. Together, our data suggests TCP enhancement of nicotine self-administration are mediated through mechanisms independent of MAO inhibition, including nicotine-paired cues and monoamine uptake inhibition.
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Affiliation(s)
- Shahrdad Lotfipour
- Department of Anatomy and Neurobiology, University of California, Irvine, California 92697, U.S.A
| | - Monica M. Arnold
- Department of Pharmacology, School of Medicine, University of California, Irvine, California 92697, U.S.A
| | - Derk J. Hogenkamp
- Department of Pharmacology, School of Medicine, University of California, Irvine, California 92697, U.S.A
| | - Kelvin W. Gee
- Department of Pharmacology, School of Medicine, University of California, Irvine, California 92697, U.S.A
| | - James D. Belluzzi
- Department of Pharmacology, School of Medicine, University of California, Irvine, California 92697, U.S.A
| | - Frances M. Leslie
- Department of Anatomy and Neurobiology, University of California, Irvine, California 92697, U.S.A
- Department of Pharmacology, School of Medicine, University of California, Irvine, California 92697, U.S.A
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