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Ramirez LA, Przybysz KR, Pitock JR, Starr EM, Yang H, Glover EJ. Attenuated incubation of ethanol-induced conditioned taste aversion in a model of dependence. Psychopharmacology (Berl) 2024; 241:1191-1203. [PMID: 38383904 PMCID: PMC11105978 DOI: 10.1007/s00213-024-06553-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 02/07/2024] [Indexed: 02/23/2024]
Abstract
RATIONALE Preclinical studies report attenuated ethanol-induced conditioned taste aversion (CTA) following chronic ethanol exposure, suggesting that tolerance develops to the aversive properties of ethanol. However, these studies are confounded by pre-exposure to the unconditioned stimulus (US; ethanol), which is well known to hinder conditioning. OBJECTIVES This study was designed to determine whether chronic ethanol exposure produces tolerance to the aversive properties of ethanol in the absence of a US pre-exposure confound. METHODS CTA was performed in adult male and female Long-Evans rats by pairing 0.1% ingested saccharin with an intraperitoneal injection of ethanol (1.5 or 2.0 g/kg) or saline. Rats were then rendered ethanol dependent using chronic intermittent ethanol (CIE) vapor exposure. Controls were exposed to room air (AIR). The effect of chronic ethanol on CTA expression and reconditioning were examined following vapor exposure. RESULTS Prior to vapor exposure, both sexes developed CTA to a comparable degree with 2.0 g/kg producing greater CTA than 1.5 g/kg ethanol. Following vapor exposure, AIR controls exhibited an increase in CTA magnitude compared to pre-vapor levels. This effect was largely absent in CIE-exposed rats. Re-conditioning after vapor exposure facilitated increased CTA magnitude to a similar degree in AIR- and CIE-exposed males. In contrast, CTA magnitude was unchanged by re-conditioning in females. CONCLUSIONS These data suggest that chronic ethanol does not facilitate tolerance to the aversive properties of ethanol but rather attenuates incubation of ethanol-induced CTA. Loss of CTA incubation suggests that CIE exposure disrupts circuits encoding aversion.
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Affiliation(s)
- Lindsey A Ramirez
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, 1601 W Taylor St, MC912, Chicago, IL, 60612, USA
| | - Kathryn R Przybysz
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, 1601 W Taylor St, MC912, Chicago, IL, 60612, USA
| | - Joseph R Pitock
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, 1601 W Taylor St, MC912, Chicago, IL, 60612, USA
| | - E Margaret Starr
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, 1601 W Taylor St, MC912, Chicago, IL, 60612, USA
| | - Hyerim Yang
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, 1601 W Taylor St, MC912, Chicago, IL, 60612, USA
| | - Elizabeth J Glover
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, 1601 W Taylor St, MC912, Chicago, IL, 60612, USA.
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Flanigan ME, Gianessi C, Castle M, Dorlean W, Sides T, Kash TL. Bed Nucleus of the Stria Terminalis (BNST) neurons containing the serotonin 5HT 2c receptor modulate operant alcohol self-administration behavior in mice. Neuropsychopharmacology 2024; 49:709-719. [PMID: 37884740 PMCID: PMC10876660 DOI: 10.1038/s41386-023-01753-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 10/05/2023] [Accepted: 10/09/2023] [Indexed: 10/28/2023]
Abstract
The serotonin 5HT2c receptor has been widely implicated in the pathophysiology of alcohol use disorder (AUD), particularly alcohol seeking and the affective consequences of chronic alcohol consumption. However, little is known about the brain sites in which 5HT2c exerts its effects on specific alcohol-related behaviors, especially in females. Here, we investigated the effects of site-specific manipulation of the 5HT2c receptor system in the BNST on operant alcohol self-administration behaviors in adult mice of both sexes, including the acquisition and maintenance of fixed-ratio responding, motivation for alcohol (progressive ratio), and quinine-adulterated responding for alcohol on a fixed-ratio schedule (punished alcohol seeking). Knockdown of 5HT2c in the BNST did not affect the acquisition or maintenance of operant alcohol self-administration, nor did it affect progressive ratio responding for alcohol. This manipulation had only a subtle effect on responding for quinine alcohol selectively in females. On the other hand, chemogenetic inhibition of BNST 5HT2c-containing neurons (BNST5HT2c) increased operant alcohol self-administration behavior in both sexes on day 2, but not day 9, of testing. It also increased operant responding for 1000 μM quinine-adulterated alcohol selectively in males. Importantly, chemogenetic inhibition of BNST5HT2c did not alter operant sucrose responding or motivation for sucrose in either sex. We then performed cell-type specific anterograde tracing, which revealed that BNST5HT2c project to similar regions in males and females, many of which have been previously implicated in AUD. We next used chemogenetics and quantification of the immediate early gene cFos to characterize the functional influence of BNST5HT2c inhibition on vlPAG activity. We show that chemogenetic inhibition of BNST5HT2c reduces vlPAG cFos in both sexes, but that this reduction is more robust in males. Together these findings suggest that BNST5HT2c neurons, and to a small extent the BNST 5HT2c receptor, serve to promote aversive responses to alcohol consumption, potentially through sex-dependent disinhibition of vlPAG neurons.
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Affiliation(s)
- Meghan E Flanigan
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Carol Gianessi
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Megan Castle
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Winifred Dorlean
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Tori Sides
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Thomas L Kash
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA.
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC, USA.
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Przybysz KR, Ramirez LA, Pitock JR, Starr EM, Yang H, Glover EJ. A translational rodent model of individual differences in sensitivity to the aversive properties of ethanol. ALCOHOL, CLINICAL & EXPERIMENTAL RESEARCH 2024; 48:516-529. [PMID: 38303664 PMCID: PMC10939790 DOI: 10.1111/acer.15267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Revised: 12/01/2023] [Accepted: 01/04/2024] [Indexed: 02/03/2024]
Abstract
BACKGROUND A strong relationship exists between individual sensitivity to the aversive properties of ethanol and risk for alcohol use disorder (AUD). Despite this, our understanding of the neurobiological mechanisms underlying the subjective response to ethanol is limited. A major contributor to this lack of knowledge is the absence of preclinical models that enable exploration of this individual variability such as is possible in studies of humans. METHODS Adult male and female Long-Evans rats were trained to associate a novel tastant (saccharin) with acute exposure to either saline or ethanol (1.5 g/kg or 2.0 g/kg i.p.) over three conditioning days using a standard conditioned taste aversion (CTA) procedure. Variability in sensitivity to ethanol-induced CTA was phenotypically characterized using a median split across the populations studied. RESULTS When examining group averages, both male and female rats exposed to saccharin paired with either dose of ethanol exhibited lower saccharin intake relative to saline controls indicative of ethanol-induced CTA. Examination of individual data revealed a bimodal distribution of responses uncovering two distinct phenotypes present in both sexes. CTA-sensitive rats exhibited a rapid and progressive reduction in saccharin intake with each successive ethanol pairing. In contrast, saccharin intake was unchanged or maintained after an initial decrease from baseline levels in CTA-resistant rats. While CTA magnitude was similar between male and female CTA-sensitive rats, among CTA-resistant animals females were more resistant to the development of ethanol-induced CTA than males. Phenotypic differences were not driven by differences in baseline saccharin intake. CONCLUSIONS These data parallel work in humans by revealing individual differences in sensitivity to the aversive properties of ethanol that emerge immediately after initial exposure to ethanol in both sexes. This model can be used in future studies to investigate the neurobiological mechanisms that confer risk for AUD.
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Affiliation(s)
- Kathryn R Przybysz
- Department of Psychiatry, Center for Alcohol Research in Epigenetics, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Lindsey A Ramirez
- Department of Psychiatry, Center for Alcohol Research in Epigenetics, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Joseph R Pitock
- Department of Psychiatry, Center for Alcohol Research in Epigenetics, University of Illinois at Chicago, Chicago, Illinois, USA
| | - E Margaret Starr
- Department of Psychiatry, Center for Alcohol Research in Epigenetics, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Hyerim Yang
- Department of Psychiatry, Center for Alcohol Research in Epigenetics, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Elizabeth J Glover
- Department of Psychiatry, Center for Alcohol Research in Epigenetics, University of Illinois at Chicago, Chicago, Illinois, USA
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Flanigan ME, Gianessi C, Castle M, Dorlean W, Sides T, Kash TL. Bed Nucleus of the Stria Terminalis (BNST) neurons containing the serotonin 5HT 2c receptor modulate operant alcohol self-administration behavior in mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.26.559653. [PMID: 37808816 PMCID: PMC10557639 DOI: 10.1101/2023.09.26.559653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
The serotonin 5HT2c receptor has been widely implicated in the pathophysiology of alcohol use disorder (AUD), particularly alcohol seeking and the affective consequences of chronic alcohol consumption. However, little is known about the brain sites in which 5HT2c exerts its effects on specific alcohol-related behaviors, especially in females. Here, we investigated the effects of site-specific manipulation of the 5HT2c receptor system in the BNST on operant alcohol self-administration behaviors in adult mice of both sexes, including the acquisition and maintenance of fixed-ratio responding, motivation for alcohol (progressive ratio), and quinine-adulterated responding for alcohol on a fixed-ratio schedule (punished alcohol seeking). Knockdown of 5HT2c in the BNST did not affect the acquisition or maintenance of operant alcohol self-administration, nor did it affect progressive ratio responding for alcohol. This manipulation had only a subtle effect on responding for quinine alcohol selectively in females. On the other hand, chemogenetic inhibition of BNST 5HT2c-containing neurons (BNST5HT2c) increased operant alcohol self-administration behavior in both sexes on day 2, but not day 9, of testing. It also increased operant responding for 1000 μM quinine-adulterated alcohol selectively in males. Importantly, chemogenetic inhibition of BNST5HT2c did not alter operant sucrose responding or motivation for sucrose in either sex. We then performed cell-type specific anterograde tracing, which revealed that BNST5HT2c project to similar regions in males and females, many of which have been previously implicated in AUD. We next used chemogenetics and quantification of the immediate early gene cFos to characterize the functional influence of BNST5HT2c inhibition on vlPAG activity. We show that chemogenetic inhibition of BNST5HT2c reduces vlPAG cFos in both sexes, but that this reduction is more robust in males. Together these findings suggest that BNST5HT2c neurons, and to a small extent the BNST 5HT2c receptor, serve to promote aversive responses to alcohol consumption, potentially through sex-dependent disinhibition of vlPAG neurons.
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Affiliation(s)
- Meghan E. Flanigan
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Carol Gianessi
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Megan Castle
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Winifred Dorlean
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Tori Sides
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Thomas L. Kash
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC, USA
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Ramirez LA, Przybysz KR, Pitock JR, Starr EM, Yang H, Glover EJ. Attenuated incubation of ethanol-induced conditioned taste aversion in a model of dependence. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.13.557582. [PMID: 37745477 PMCID: PMC10515951 DOI: 10.1101/2023.09.13.557582] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Rationale Preclinical studies report attenuated ethanol-induced conditioned taste aversion (CTA) following chronic ethanol exposure, suggesting that tolerance develops to the aversive properties of ethanol. However, these studies are confounded by pre-exposure to the unconditioned stimulus (US; ethanol), which is well known to hinder conditioning. Objectives This study was designed to determine whether chronic ethanol exposure produces tolerance to the aversive properties of ethanol in the absence of a US pre-exposure confound. Methods CTA was performed in adult male and female Long-Evans rats by pairing 0.1% ingested saccharin with an intraperitoneal injection of ethanol (1.5 or 2.0 g/kg) or saline. Rats were then rendered ethanol dependent using chronic intermittent ethanol (CIE) vapor exposure. Controls were exposed to room air (AIR). The effect of chronic ethanol on CTA expression and reconditioning were examined following vapor exposure. Results Prior to vapor exposure, both sexes developed CTA to a comparable degree with 2.0 g/kg producing greater CTA than 1.5 g/kg ethanol. Following vapor exposure, AIR controls exhibited an increase in CTA magnitude compared to pre-vapor levels. This effect was absent in CIE-exposed rats. These group differences were eliminated upon re-conditioning after vapor exposure. Conclusions These data suggest that chronic ethanol does not facilitate tolerance to the aversive properties of ethanol but rather, attenuates incubation of ethanol-induced CTA. Loss of CTA incubation suggests that CIE exposure disrupts circuits encoding aversion.
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Affiliation(s)
- Lindsey A Ramirez
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, USA
| | - Kathryn R Przybysz
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, USA
| | - Joseph R Pitock
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, USA
| | - E Margaret Starr
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, USA
| | - Hyerim Yang
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, USA
| | - Elizabeth J Glover
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, USA
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Przybysz KR, Ramirez LA, Pitock JR, Starr EM, Yang H, Glover EJ. A translational rodent model of individual differences in sensitivity to the aversive properties of ethanol. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.08.544209. [PMID: 37333122 PMCID: PMC10274910 DOI: 10.1101/2023.06.08.544209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Background A strong relationship exists between individual sensitivity to the aversive properties of ethanol and risk for alcohol use disorder (AUD). Despite this, our understanding of the neurobiological mechanisms underlying subjective response to ethanol is relatively poor. A major contributor to this is the absence of preclinical models that enable exploration of this individual variability similar to studies performed in humans. Methods Adult male and female Long-Evans rats were trained to associate a novel tastant (saccharin) with acute exposure to either saline or ethanol (1.5 g/kg or 2.0 g/kg i.p.) over three conditioning days using a standard conditioned taste aversion (CTA) procedure. Variability in sensitivity to ethanol-induced CTA was phenotypically characterized using a median split across the populations studied. Results When examining group averages, both male and female rats that had saccharin paired with either dose of ethanol exhibited reduced saccharin intake relative to saline controls of ethanol-induced CTA. Examination of individual data revealed a bimodal distribution of responses uncovering two distinct phenotypes present in both sexes. CTA-sensitive rats exhibited a rapid and progressive reduction in saccharin intake with each successive ethanol pairing. In contrast, saccharin intake was unchanged or maintained after an initial decrease from baseline levels in CTA-resistant rats. While CTA magnitude was similar between male and female CTA-sensitive rats, CTA-resistant females were more resistant to the development of ethanol-induced CTA than their male counterparts. Phenotypic differences were not driven by differences in baseline saccharin intake. CTA sensitivity correlated with behavioral signs of intoxication in only a subset of rats. Conclusions These data parallel work in humans by revealing individual differences in sensitivity to the aversive properties of ethanol that emerge immediately after initial exposure to ethanol in both sexes. This model can be leveraged in future studies to investigate the neurobiological mechanisms that confer risk for AUD.
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Affiliation(s)
- Kathryn R Przybysz
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, USA
| | - Lindsey A Ramirez
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, USA
| | - Joseph R Pitock
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, USA
| | - E Margaret Starr
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, USA
| | - Hyerim Yang
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, USA
| | - Elizabeth J Glover
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, USA
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Harris AC, Muelken P, Alcheva A, Stepanov I, LeSage MG. Cigarette Smoke Extract, but Not Electronic Cigarette Aerosol Extract, Inhibits Monoamine Oxidase in vitro and Produces Greater Acute Aversive/Anhedonic Effects Than Nicotine Alone on Intracranial Self-Stimulation in Rats. Front Neurosci 2022; 16:868088. [PMID: 35712461 PMCID: PMC9196039 DOI: 10.3389/fnins.2022.868088] [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: 02/02/2022] [Accepted: 04/25/2022] [Indexed: 12/14/2022] Open
Abstract
Conventional tobacco cigarettes appear to have greater abuse liability than non-combusted products such as electronic cigarettes (ECs) and nicotine replacement therapy (NRT). This may be due to the higher levels of behaviorally active non-nicotine constituents [e.g., monoamine oxidase (MAO) inhibitors such as β-carbolines] in cigarette smoke (CS) compared to non-combusted products. To evaluate this hypothesis, the current studies compared the relative abuse liability of CS and EC aerosol extracts containing nicotine and a range of non-nicotine constituents to that of nicotine alone (NRT analog) using intracranial self-stimulation (ICSS) in rats. Effects of formulations on brain MAO activity in vitro and ex vivo were also studied to evaluate the potential role of MAO inhibition in the ICSS study. CS extract contained higher levels of several behaviorally active non-nicotine constituents (e.g., the β-carbolines norharmane and harmane) than EC extract. Nicotine alone reduced ICSS thresholds at a moderate nicotine dose, suggesting a reinforcement-enhancing effect that may promote abuse liability, and elevated ICSS thresholds at a high nicotine dose, suggesting an aversive/anhedonic effect that may limit abuse liability. CS extract elevated ICSS thresholds to a greater degree than nicotine alone at high nicotine doses. Effects of EC extract on ICSS did not differ from those of nicotine alone. Finally, CS extract significantly inhibited MAO-A and MAO-B activity in vitro, whereas EC extract and nicotine alone did not. None of the formulations inhibited MAO measured ex vivo. These findings indicate greater acute aversive/anhedonic effects for CS extract compared to nicotine alone, suggesting lower abuse liability. Although confirmation of our findings using other dosing regimens, preclinical addiction models, and tobacco product extracts is needed, these findings suggest that the centrally-mediated effects of MAO inhibitors and other non-nicotine constituents may not account for the greater abuse liability of cigarettes compared to non-combusted products. Nonetheless, identifying the specific constituent(s) mediating the effects of CS extracts in this study could help clarify mechanisms mediating tobacco addiction and inform FDA product standards.
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Affiliation(s)
- Andrew C. Harris
- Hennepin Healthcare Research Institute, Minneapolis, MN, United States,Department of Medicine, University of Minnesota, Minneapolis, MN, United States,Department of Psychology, University of Minnesota, Minneapolis, MN, United States,*Correspondence: Andrew C. Harris,
| | - Peter Muelken
- Hennepin Healthcare Research Institute, Minneapolis, MN, United States
| | - Aleksandra Alcheva
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, United States
| | - Irina Stepanov
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, United States
| | - Mark G. LeSage
- Hennepin Healthcare Research Institute, Minneapolis, MN, United States,Department of Medicine, University of Minnesota, Minneapolis, MN, United States,Department of Psychology, University of Minnesota, Minneapolis, MN, United States
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The Paradoxical Effect Hypothesis of Abused Drugs in a Rat Model of Chronic Morphine Administration. J Clin Med 2021; 10:jcm10153197. [PMID: 34361981 PMCID: PMC8348660 DOI: 10.3390/jcm10153197] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 07/13/2021] [Accepted: 07/19/2021] [Indexed: 12/22/2022] Open
Abstract
A growing body of studies has recently shown that abused drugs could simultaneously induce the paradoxical effect in reward and aversion to influence drug addiction. However, whether morphine induces reward and aversion, and which neural substrates are involved in morphine’s reward and aversion remains unclear. The present study first examined which doses of morphine can simultaneously produce reward in conditioned place preference (CPP) and aversion in conditioned taste aversion (CTA) in rats. Furthermore, the aversive dose of morphine was determined. Moreover, using the aversive dose of 10 mg/kg morphine tested plasma corticosterone (CORT) levels and examined which neural substrates were involved in the aversive morphine-induced CTA on conditioning, extinction, and reinstatement. Further, we analyzed c-Fos and p-ERK expression to demonstrate the paradoxical effect—reward and aversion and nonhomeostasis or disturbance by morphine-induced CTA. The results showed that a dose of more than 20 mg/kg morphine simultaneously induced reward in CPP and aversion in CTA. A dose of 10 mg/kg morphine only induced the aversive CTA, and it produced higher plasma CORT levels in conditioning and reacquisition but not extinction. High plasma CORT secretions by 10 mg/kg morphine-induced CTA most likely resulted from stress-related aversion but were not a rewarding property of morphine. For assessments of c-Fos and p-ERK expression, the cingulate cortex 1 (Cg1), prelimbic cortex (PrL), infralimbic cortex (IL), basolateral amygdala (BLA), nucleus accumbens (NAc), and dentate gyrus (DG) were involved in the morphine-induced CTA, and resulted from the aversive effect of morphine on conditioning and reinstatement. The c-Fos data showed fewer neural substrates (e.g., PrL, IL, and LH) on extinction to be hyperactive. In the context of previous drug addiction data, the evidence suggests that morphine injections may induce hyperactivity in many neural substrates, which mediate reward and/or aversion due to disturbance and nonhomeostasis in the brain. The results support the paradoxical effect hypothesis of abused drugs. Insight from the findings could be used in the clinical treatment of drug addiction.
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McNamara TA, Ito R. Relationship between voluntary ethanol drinking and approach-avoidance biases in the face of motivational conflict: novel sex-dependent associations in rats. Psychopharmacology (Berl) 2021; 238:1817-1832. [PMID: 33783557 DOI: 10.1007/s00213-021-05810-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 03/01/2021] [Indexed: 12/18/2022]
Abstract
RATIONALE Aberrant approach-avoidance conflict processing may contribute to compulsive seeking that characterizes addiction. Exploration of the relationship between drugs of abuse and approach-avoidance behavior remains limited, especially with ethanol. OBJECTIVES To investigate the effects of voluntary ethanol consumption on approach-avoidance conflict behavior and to examine the potential approach/avoidance bias to predict drinking in male and female rats. METHODS Long-Evans rats consumed ethanol for 5 weeks under the intermittent access two-bottle choice (IA2BC) paradigm. Approach-avoidance tendencies were assessed before and after IA2BC drinking using a previously established cued approach-avoidance conflict maze task and the elevated plus maze (EPM). RESULTS Female rats displayed higher consumption of and preference for ethanol than males. In the conflict task, males showed greater approach bias towards cues predicting conflict than females. In females only, a median split and regression analysis of cued-conflict preference scores revealed that the more conflict-avoidant group displayed higher intake and preference for ethanol in the first few weeks of drinking. In both sexes, ethanol drinking did not affect cued-conflict preference, but ethanol exposure led to increased time spent in the central hub in the males only. Finally, anxiety levels in EPM predicted subsequent onset of ethanol drinking in males only. CONCLUSIONS Our results highlight sex and individual differences in both drinking and approach-avoidance bias in the face of cued conflict and further suggest that cued-conflict preference should be examined as a potential predictor of ethanol drinking. Ethanol exposure may also affect the timing of decision-making in the face of conflict.
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Affiliation(s)
- Tanner A McNamara
- Department of Psychology, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, M1C 1A4, Canada
| | - Rutsuko Ito
- Department of Psychology, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, M1C 1A4, Canada. .,Department of Cell and Systems Biology, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, M1C 1A4, Canada.
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Minervini V, Tye CB, Ghodrati S, France CP. Effects of remifentanil/histamine mixtures in rats responding under a choice procedure. Behav Pharmacol 2021; 32:278-285. [PMID: 33491991 PMCID: PMC8119289 DOI: 10.1097/fbp.0000000000000610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Intravenous drug self-administration remains the 'gold standard' for assessing abuse liability. Failure of a drug to maintain self-administration might indicate the absence of positive reinforcing effects but might also indicate the presence of aversive effects. Sensitivity to aversive and punishing effects of drugs (as well as nondrug stimuli) might collectively determine the likelihood of use, abuse and relapse. Using a choice procedure, this study compared the effects of remifentanil (mu opioid receptor agonist; 0.001-0.01 mg/kg/infusion) and histamine (H1-4 receptor agonist; 0.32-3.2 mg/kg/infusion), alone and in mixtures, to test the hypothesis that remifentanil/histamine mixtures are less reinforcing compared with remifentanil alone and less punishing compared with histamine alone. Male Sprague-Dawley rats (n = 10) chose between an intravenous infusion + a pellet and a pellet alone. Rats were indifferent to saline, chose remifentanil + a pellet over a pellet alone, and chose a pellet alone over histamine + a pellet. The effects of remifentanil/histamine mixtures generally were different from the constituent doses of histamine alone but not from remifentanil alone. A mixture containing 3.2 mg/kg/infusion histamine and either 0.001 or 0.0032 mg/kg/infusion remifentanil was not different from saline but was different from the effects of the constituent dose, insofar as choice increased compared with 3.2 mg/kg/infusion histamine alone and decreased compared with 0.001 or 0.0032 mg/kg/infusion remifentanil alone. Reinforcing doses of remifentanil combined with punishing doses of histamine can yield mixtures that are neither preferred nor avoided, offering 'proof-of-principle' for using drug mixtures to avoid adverse effects of opioid receptor agonists.
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Affiliation(s)
| | | | | | - Charles P France
- Departments of Pharmacology
- Departments of Psychiatry, The Addiction Research, Treatment and Training Center of Excellence, University of Texas Health Science Center at San Antonio, Texas, USA
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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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12
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Carr KD. Homeostatic regulation of reward via synaptic insertion of calcium-permeable AMPA receptors in nucleus accumbens. Physiol Behav 2020; 219:112850. [PMID: 32092445 PMCID: PMC7108974 DOI: 10.1016/j.physbeh.2020.112850] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 01/23/2020] [Accepted: 02/18/2020] [Indexed: 10/25/2022]
Abstract
The incentive effects of food and related cues are determined by stimulus properties and the internal state of the organism. Enhanced hedonic reactivity and incentive motivation in energy deficient subjects have been demonstrated in animal models and humans. Defining the neurobiological underpinnings of these state-based modulatory effects could illuminate fundamental mechanisms of adaptive behavior, as well as provide insight into maladaptive consequences of weight loss dieting and the relationship between disturbed eating behavior and substance abuse. This article summarizes research of our laboratory aimed at identifying neuroadaptations induced by chronic food restriction (FR) that increase the reward magnitude of drugs and associated cues. The main findings are that FR decreases basal dopamine (DA) transmission, upregulates signaling downstream of the D1 DA receptor (D1R), and triggers synaptic incorporation of calcium-permeable AMPA receptors (CP-AMPARs) in the nucleus accumbens (NAc). Selective antagonism of CP-AMPARs decreases excitatory postsynaptic currents in NAc medium spiny neurons of FR rats and blocks the enhanced rewarding effects of d-amphetamine and a D1R, but not a D2R, agonist. These results suggest that FR drives CP-AMPARs into the synaptic membrane of D1R-expressing MSNs, possibly as a homeostatic response to reward loss. FR subjects also display diminished aversion for contexts associated with LiCl treatment and centrally infused cocaine. An encompassing, though speculative, hypothesis is that NAc synaptic incorporation of CP-AMPARs in response to food scarcity and other forms of sustained reward loss adaptively increases incentive effects of reward stimuli and, at the same time, diminishes responsiveness to aversive stimuli that have potential to interfere with goal pursuit.
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Affiliation(s)
- Kenneth D Carr
- Departments of Psychiatry and Biochemistry and Molecular Pharmacology, New York University School of Medicine, 435 East 30th Street, New York, NY 10016, United States.
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13
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Riley AL, Nelson KH, To P, López-Arnau R, Xu P, Wang D, Wang Y, Shen HW, Kuhn DM, Angoa-Perez M, Anneken JH, Muskiewicz D, Hall FS. Abuse potential and toxicity of the synthetic cathinones (i.e., “Bath salts”). Neurosci Biobehav Rev 2020; 110:150-173. [DOI: 10.1016/j.neubiorev.2018.07.015] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 06/14/2018] [Accepted: 07/24/2018] [Indexed: 01/22/2023]
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14
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Punishment and reinforcement by opioid receptor agonists in a choice procedure in rats. Behav Pharmacol 2020; 30:335-342. [PMID: 30320606 DOI: 10.1097/fbp.0000000000000436] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Intravenous (i.v.) drug self-administration remains the 'gold standard' for assessing abuse potential of drugs. Failure of a drug to maintain self-administration might indicate merely the absence of positive-reinforcing effects but might also indicate presence of aversive effects. Sensitivity to aversive effects is thought to affect the initiation and maintenance of drug use as well as relapse. Choice procedures are used to study positive-reinforcing effects of drugs and to a much lesser extent to study punishing effects of drugs. Experiment 1 compared the μ-opioid receptor agonist remifentanil (0.001-0.01 mg/kg/infusion), the κ-opioid receptor agonist spiradoline (0.0056-0.056 mg/kg/infusion), and histamine (1.0 mg/kg/infusion) in rats choosing between a food pellet only and an i.v. infusion+a food pellet. To test whether a history with one punishing drug affects the punishing effects of a second drug, experiment 2 compared sensitivity with spiradoline in rats with and without a history of histamine punishment. All rats predominantly chose a pellet alone when histamine+a pellet was the alternative, and they predominantly chose remifentanil+a pellet over a pellet alone. In experiment 2, spiradoline was punishing in rats with a history of histamine punishment but not drug-naive rats. This food choice procedure is sensitive to reinforcing and punishing effects of different drugs in the same subjects, suggesting that the procedure is well-suited for studying drug mixtures (e.g. μ and κ agonists) and the impact of different physiological conditions (e.g. pain) on reinforcement and punishment.
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Zhao YN, Yan YD, Wang CY, Qu WM, Jhou TC, Huang ZL, Yang SR. The Rostromedial Tegmental Nucleus: Anatomical Studies and Roles in Sleep and Substance Addictions in Rats and Mice. Nat Sci Sleep 2020; 12:1215-1223. [PMID: 33380853 PMCID: PMC7769149 DOI: 10.2147/nss.s278026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 11/23/2020] [Indexed: 12/15/2022] Open
Abstract
The rostromedial tegmental nucleus (RMTg), a brake of the dopamine system, is specifically activated by aversive stimuli, such as foot shock. It is principally composed of gamma-aminobutyric acid neurons. However, there is no exact location of the RMTg on the brain stereotaxic atlas. The RMTg can be defined by c-Fos staining elicited by psychostimulants, the position of retrograde-labeled neurons stained by injections into the ventral tegmental area (VTA), the terminal field formed by axons from the lateral habenula, and some molecular markers identified as specifically expressed in the RMTg such as FoxP1. The RMTg receives a broad range of inputs and produces diverse outputs, which indicates that the RMTg has multiple functions. First, the RMTg plays an essential role for non-rapid eye movement sleep. Additionally, the RMTg serves a vital role in response to addiction. Opiates increase the firing rates of dopaminergic neurons in the VTA by acting on μ-opioid receptors on RMTg neurons and their terminals inside the VTA. In this review, we summarize the recent research advances on the anatomical location of the RMTg in rats and mice, its projections, and its regulation of sleep-wake behavior and addiction.
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Affiliation(s)
- Ya-Nan Zhao
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, People's Republic of China
| | - Yu-Dong Yan
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, People's Republic of China
| | - Chen-Yao Wang
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, People's Republic of China
| | - Wei-Min Qu
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, People's Republic of China
| | - Thomas C Jhou
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA
| | - Zhi-Li Huang
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, People's Republic of China
| | - Su-Rong Yang
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, People's Republic of China
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16
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Assessing the motivational effects of ethanol in mice using a discrete-trial current-intensity intracranial self-stimulation procedure. Drug Alcohol Depend 2019; 207:107806. [PMID: 31864164 PMCID: PMC6939988 DOI: 10.1016/j.drugalcdep.2019.107806] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 11/18/2019] [Accepted: 12/05/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Alcohol (ethanol) produces both rewarding and aversive effects, and sensitivity to these effects is associated with risk for an alcohol use disorder (AUD). Measurement of these motivational effects in animal models is an important but challenging aspect of preclinical research into the neurobiology of AUD. Here, we evaluated whether a discrete-trial current-intensity intracranial self-stimulation (ICSS) procedure can be used to assess both reward-enhancing and aversive responses to ethanol in mice. METHODS Male and female C57BL/6J mice were surgically implanted with bipolar stimulating electrodes targeting the medial forebrain bundle and trained on a discrete-trial current-intensity ICSS procedure. Mice were tested for changes in response thresholds after various doses of ethanol (0.5 g/kg-1.75 g/kg; n = 5-7 per dose), using a Latin square design. RESULTS A 1 g/kg dose of ethanol produced a significant reward-enhancement (i.e., lowered response thresholds), whereas a 1.75 g/kg dose produced an aversive effect (elevated response thresholds). Ethanol doses from 1 to 1.75 g/kg increased response latencies as compared to saline treatment. CONCLUSIONS The discrete-trial current-intensity ICSS procedure is an effective assay for measuring both reward-enhancing responses to ethanol as well as aversive responses in the same animal. This should prove to be a useful tool for assessing the effects of experimental manipulations on the motivational effects of ethanol in mice.
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He ABH, Huang CL, Kozłowska A, Chen JC, Wu CW, Huang ACW, Liu YQ. Involvement of neural substrates in reward and aversion to methamphetamine addiction: Testing the reward comparison hypothesis and the paradoxical effect hypothesis of abused drugs. Neurobiol Learn Mem 2019; 166:107090. [PMID: 31521799 DOI: 10.1016/j.nlm.2019.107090] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 08/23/2019] [Accepted: 09/11/2019] [Indexed: 11/17/2022]
Abstract
Clinical studies of drug addiction focus on the reward impact of abused drugs that produces compulsive drug-seeking behavior and drug dependence. However, a small amount of research has examined the opposite effect of aversion to abused drugs to balance the reward effect for drug taking. An aversive behavioral model of abused drugs in terms of conditioned taste aversion (CTA) was challenged by the reward comparison hypothesis (Grigson, 1997). To test the reward comparison hypothesis, the present study examined the rewarding or aversive neural substrates involved in methamphetamine-induced conditioned suppression. The behavioral data showed that methamphetamine induced conditioned suppression on conditioning and reacquisition but extinguished it on extinction. A higher level of stressful aversive corticosterone occurred on conditioning and reacquisition but not extinction. The c-Fos or p-ERK immunohistochemical activity showed that the cingulated cortex area 1 (Cg1), infralimbic cortex (IL), prelimbic cortex (PrL), basolateral amygdala (BLA), nucleus accumbens (NAc), and dentate gyrus (DG) of the hippocampus were overexpressed in aversive CTA induced by methamphetamine. These data may indicate that the Cg1, IL, PrL, BLA, NAc, and DG probably mediated the paradoxical effect-reward and aversion. Altogether, our data conflicted with the reward comparison hypothesis, and methamphetamine may simultaneously induce the paradoxical effect of reward and aversion in the brain to support the paradoxical effect hypothesis of abused drugs. The present data implicate some insights for drug addiction in clinical aspects.
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Affiliation(s)
- Alan Bo Han He
- Department of Psychology, Fo Guang University, Yilan County 26247, Taiwan
| | - Chung Lei Huang
- Department of Psychology, Fo Guang University, Yilan County 26247, Taiwan
| | - Anna Kozłowska
- Department of Human Physiology, School Medicine, Collegium Medicum, University of Warmia and Mazury in Olsztyn, Warszawska Av, 30, 10-082 Olsztyn, Poland
| | - Jun Chien Chen
- Department of Substance Abuse and Psychiatry, Tri-Service General Hospital Beitou Branch, Taipei 11243, Taiwan
| | - Chi-Wen Wu
- Department of Psychology, Fo Guang University, Yilan County 26247, Taiwan; Department of Pharmacy, Keelung Hospital, Ministry of Health and Welfare, Keelung City 20148, Taiwan
| | | | - Yu Qin Liu
- Department of Psychology, Fo Guang University, Yilan County 26247, Taiwan
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18
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Nelson KH, Manke HN, Imanalieva A, Rice KC, Riley AL. Sex differences in α-pyrrolidinopentiophenone (α-PVP)-induced taste avoidance, place preference, hyperthermia and locomotor activity in rats. Pharmacol Biochem Behav 2019; 185:172762. [PMID: 31445057 DOI: 10.1016/j.pbb.2019.172762] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 08/19/2019] [Accepted: 08/19/2019] [Indexed: 12/13/2022]
Abstract
RATIONALE The majority of synthetic cathinone research has used only male subjects, and as a result there are few studies assessing the impact of biological sex on their effects. OBJECTIVES The current work extends the characterization of the second-generation synthetic cathinone, α-PVP, by investigating how biological sex impacts α-PVP's aversive and rewarding effects important to its use and potential abuse. METHODS A combined conditioned taste avoidance/conditioned place preference preparation was utilized in which adult male and female Sprague Dawley rats were injected with 1.5, 3 or 6 mg/kg of racemic α-PVP or vehicle (saline) (IP). Following a 24-day washout period, rats were then tested for thermoregulatory effects of α-PVP using subcutaneous microchips to measure body temperature changes over the course of 8 h. This was followed 21 days later by assessments for α-PVP-induced locomotor activity and stereotypies over a 1-h session. RESULTS Dose-dependent conditioned taste avoidance was evident in both males and females, although females displayed weaker avoidance at 3 mg/kg compared to males. Males displayed a dose-dependent conditioned place preference, while females did not form a place preference at any dose. α-PVP elicited dose- and time-dependent hyperthermia, with males displaying a faster on-set and delayed off-set compared to females. α-PVP also produced dose- and time-dependent increases in locomotor activity (F > M) and stereotypies (M > F). CONCLUSIONS As described, males displayed greater rewarding (as indexed by place preference conditioning) and aversive (as indexed by taste avoidance, hyperthermia and stereotypies) effects of α-PVP. Although comparisons between males and females in α-PVP self-administration have not been reported, these data suggest that males may be more likely to use the drug. The implications for sex differences in human use of α-PVP were discussed.
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Affiliation(s)
- Katharine H Nelson
- Psychopharmacology Laboratory, Center for Behavioral Neuroscience, American University, 4400 Massachusetts Ave, NW, Washington, DC 20016, USA.
| | - Hayley N Manke
- Psychopharmacology Laboratory, Center for Behavioral Neuroscience, American University, 4400 Massachusetts Ave, NW, Washington, DC 20016, USA
| | - Aikerim Imanalieva
- Psychopharmacology Laboratory, Center for Behavioral Neuroscience, American University, 4400 Massachusetts Ave, NW, Washington, DC 20016, USA
| | - Kenner C Rice
- Drug Design and Synthesis Section, National Institute on Drug Abuse (NIDA), National Institute on Alcohol Abuse and Alcoholism (NIAAA), Bethesda, MD 20892, USA
| | - Anthony L Riley
- Psychopharmacology Laboratory, Center for Behavioral Neuroscience, American University, 4400 Massachusetts Ave, NW, Washington, DC 20016, USA.
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Fu R, Zuo W, Shiwalkar N, Mei Q, Fan Q, Chen X, Li J, Bekker A, Ye JH. Alcohol withdrawal drives depressive behaviors by activating neurons in the rostromedial tegmental nucleus. Neuropsychopharmacology 2019; 44:1464-1475. [PMID: 30928995 PMCID: PMC6784902 DOI: 10.1038/s41386-019-0378-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 03/18/2019] [Accepted: 03/24/2019] [Indexed: 01/01/2023]
Abstract
Rostromedial tegmental nucleus (RMTg) GABA neurons exert a primary inhibitory drive onto midbrain dopamine neurons and are excited by a variety of aversive stimuli. There is, however, little evidence that the RMTg-ventral tegmental area (VTA)-nucleus accumbens shell (Acb) circuit plays a role in the aversive consequences of alcohol withdrawal. This study was performed in adult male Long-Evans rats at 48-h withdrawal from chronic alcohol drinking in the intermittent schedule. These rats displayed clear anhedonia and depression-like behaviors, as measured with the sucrose preference, and forced swimming tests. These aberrant behaviors were accompanied by a substantial increase in cFos expression in the VTA-projecting RMTg neurons, identified by a combination of immunohistochemistry and retrograde-tracing techniques. Pharmacological or chemogenetic inhibition of RMTg neurons mitigated the anhedonia and depression-like behaviors. Ex vivo electrophysiological data showed that chemogenetic inactivation of RMTg neurons reduced GABA release and accelerated spontaneous firings of VTA dopamine neurons. Finally, using a functional hemispheric disconnection procedure, we demonstrated that inhibition of unilateral RMTg, when combined with activation of D1 and D2 dopamine receptors in the contralateral (but not ipsilateral) Acb, mitigated the anhedonia and depression-like behaviors in alcohol-withdrawal rats. These data show that the integrity in the RMTg-VTA-Acb pathway in a single hemisphere is sufficient to elicit depression-like behavior during ethanol-withdrawal. Overall, the present results reveal that the RMTg-VTA-Acb pathway plays a crucial role in the depression-like behavior in animals undergoing alcohol withdrawal, further advocating the RMTg as a potential therapeutic target for alcoholism.
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Affiliation(s)
- Rao Fu
- Department of Anesthesiology, Department of Pharmacology, Physiology and Neuroscience, Rutgers, The State University of New Jersey, New Jersey Medical School, 185 South Orange Ave, Newark, NJ, 07103, USA
| | - Wanhong Zuo
- Department of Anesthesiology, Department of Pharmacology, Physiology and Neuroscience, Rutgers, The State University of New Jersey, New Jersey Medical School, 185 South Orange Ave, Newark, NJ, 07103, USA
| | - Nimisha Shiwalkar
- Department of Anesthesiology, Department of Pharmacology, Physiology and Neuroscience, Rutgers, The State University of New Jersey, New Jersey Medical School, 185 South Orange Ave, Newark, NJ, 07103, USA
| | - Qinghua Mei
- Department of Anesthesiology, Department of Pharmacology, Physiology and Neuroscience, Rutgers, The State University of New Jersey, New Jersey Medical School, 185 South Orange Ave, Newark, NJ, 07103, USA
| | - Qing Fan
- Department of Anesthesiology, Department of Pharmacology, Physiology and Neuroscience, Rutgers, The State University of New Jersey, New Jersey Medical School, 185 South Orange Ave, Newark, NJ, 07103, USA
| | - Xuejun Chen
- Department of Anesthesiology, Department of Pharmacology, Physiology and Neuroscience, Rutgers, The State University of New Jersey, New Jersey Medical School, 185 South Orange Ave, Newark, NJ, 07103, USA
| | - Jing Li
- Department of Anesthesiology, Department of Pharmacology, Physiology and Neuroscience, Rutgers, The State University of New Jersey, New Jersey Medical School, 185 South Orange Ave, Newark, NJ, 07103, USA
| | - Alex Bekker
- Department of Anesthesiology, Department of Pharmacology, Physiology and Neuroscience, Rutgers, The State University of New Jersey, New Jersey Medical School, 185 South Orange Ave, Newark, NJ, 07103, USA
| | - Jiang-Hong Ye
- Department of Anesthesiology, Department of Pharmacology, Physiology and Neuroscience, Rutgers, The State University of New Jersey, New Jersey Medical School, 185 South Orange Ave, Newark, NJ, 07103, USA.
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Glucagon-Like Peptide-1 Receptor Agonist Treatment Does Not Reduce Abuse-Related Effects of Opioid Drugs. eNeuro 2019; 6:eN-NRS-0443-18. [PMID: 31058214 PMCID: PMC6498420 DOI: 10.1523/eneuro.0443-18.2019] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 02/19/2019] [Accepted: 02/28/2019] [Indexed: 12/29/2022] Open
Abstract
Dependence on opioids and the number of opioid overdose deaths are serious and escalating public health problems, but medication-assisted treatments for opioid addiction remain inadequate for many patients. Glucagon-like pepide-1 (GLP-1) is a gut hormone and neuropeptide with actions in peripheral tissues and in the brain, including regulation of blood glucose and food intake. GLP-1 analogs, which are approved diabetes medications, can reduce the reinforcing and rewarding effects of alcohol, cocaine, amphetamine, and nicotine in rodents. Investigations on effects of GLP-1 analogs on opioid reward and reinforcement have not been reported. We assessed the effects of the GLP-1 receptor agonist Exendin-4 (Ex4) on opioid-related behaviors in male mice, i.e., morphine-conditioned place preference (CPP), intravenous self-administration (IVSA) of the short-acting synthetic opioid remifentanil, naltrexone-precipitated morphine withdrawal, morphine analgesia (male and female mice), and locomotor activity. Ex4 treatment had no effect on morphine-induced CPP, withdrawal, or hyperlocomotion. Ex4 failed to decrease remifentanil self-administration, if anything reinforcing effects of remifentanil appeared increased in Ex4-treated mice relative to saline. Ex4 did not significantly affect analgesia. In contrast, Ex4 dose dependently decreased oral alcohol self-administration, and suppressed spontaneous locomotor activity. Taken together, Ex4 did not attenuate the addiction-related behavioral effects of opioids, indicating that GLP-1 analogs would not be useful medications in the treatment of opioid addiction. This difference between opioids and other drug classes investigated to date may shed light on the mechanism of action of GLP-1 receptor treatment in the addictive effects of alcohol, central stimulants, and nicotine.
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21
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Loney GC, Angelyn H, Cleary LM, Meyer PJ. Nicotine Produces a High-Approach, Low-Avoidance Phenotype in Response to Alcohol-Associated Cues in Male Rats. Alcohol Clin Exp Res 2019; 43:1284-1295. [PMID: 30958564 DOI: 10.1111/acer.14043] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 04/01/2019] [Indexed: 11/28/2022]
Abstract
BACKGROUND Nicotine and alcohol use are highly comorbid. Modulation of drug-paired extrinsic and intrinsic cues likely plays a role in this interaction, as cues can acquire motivational properties and augment drug seeking. The motivational properties of cues can be measured through Pavlovian conditioning paradigms, in which cues either elicit approach following pairing with the reinforcing properties of alcohol or elicit avoidance following pairing with the aversive consequences of alcohol. The present experiments tested whether nicotine would enhance the incentive properties of an appetitive ethanol (EtOH) cue and diminish the avoidance of an aversive EtOH cue in Pavlovian paradigms. METHODS In experiment 1, male Long-Evans rats with or without prior chronic intermittent access to EtOH were administered nicotine or saline injections prior to Pavlovian conditioned approach (PavCA) sessions, during which conditioned approach to the cue ("sign-tracking") or the EtOH delivery location ("goal-tracking") was measured. In experiment 2, male Long-Evans rats were administered nicotine or saline injections prior to pairing a flavor cue with increasing doses of EtOH (i.p.) in an adaptation of the conditioned taste avoidance (CTA) paradigm. RESULTS Results from PavCA indicate that, regardless of EtOH exposure, nicotine enhanced responding elicited by EtOH-paired cues with no effect on a similar cue not explicitly paired with EtOH. Furthermore, nicotine reduced sensitivity to EtOH-induced CTA, as indicated by a rightward shift in the dose-response curve of passively administered EtOH. The ED50 , or the dose of EtOH that produced a 50% reduction in intake relative to baseline, was significantly higher in nicotine-treated rats compared to saline-treated rats. CONCLUSIONS We conclude that nicotine increases the approach and diminishes the avoidance elicited by Pavlovian cues paired, respectively, with the reinforcing and aversive properties of EtOH consumption in male rats. As such, nicotine may enhance alcoholism liability by engendering an attentional bias toward cues that predict the reinforcing outcomes of drinking.
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Affiliation(s)
- Gregory C Loney
- Department of Psychology, Center for Ingestive Behavior Research, University at Buffalo, Buffalo, New York
| | - Hailley Angelyn
- Department of Psychology, Center for Ingestive Behavior Research, University at Buffalo, Buffalo, New York
| | - Liam M Cleary
- Department of Psychology, Center for Ingestive Behavior Research, University at Buffalo, Buffalo, New York
| | - Paul J Meyer
- Department of Psychology, Center for Ingestive Behavior Research, University at Buffalo, Buffalo, New York
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Ethanol Conditioned Taste Aversion in High Drinking in the Dark Mice. Brain Sci 2019; 9:brainsci9010002. [PMID: 30609665 PMCID: PMC6356868 DOI: 10.3390/brainsci9010002] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 12/20/2018] [Accepted: 12/20/2018] [Indexed: 11/24/2022] Open
Abstract
Two independent lines of High Drinking in the Dark (HDID-1, HDID-2) mice have been bred to reach high blood alcohol levels after a short period of binge-like ethanol drinking. Male mice of both lines were shown to have reduced sensitivity to develop a taste aversion to a novel flavor conditioned by ethanol injections as compared with their unselected HS/NPT founder stock. We have subsequently developed inbred variants of each line. The current experiments established that reduced ethanol-conditioned taste aversion is also seen in the inbred variants, in both males and females. In other experiments, we asked whether HDID mice would ingest sufficient doses of ethanol to lead to a conditioned taste aversion upon retest. Different manipulations were used to elevate consumption of ethanol on initial exposure. Access to increased ethanol concentrations, to multiple tubes of ethanol, and fluid restriction to increase thirst motivation all enhanced initial drinking of ethanol. Each condition led to reduced intake the next day, consistent with a mild conditioned taste aversion. These experiments support the conclusion that one reason contributing to the willingness of HDID mice to drink to the point of intoxication is a genetic insensitivity to the aversive effects of ethanol.
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23
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Riley AL, Hempel BJ, Clasen MM. Sex as a biological variable: Drug use and abuse. Physiol Behav 2017; 187:79-96. [PMID: 29030249 DOI: 10.1016/j.physbeh.2017.10.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 09/15/2017] [Accepted: 10/07/2017] [Indexed: 01/11/2023]
Abstract
The study of sex as a biological variable is a necessary emphasis across a wide array of endpoints, including basic neuroscience, medicine, mental health, physiology and behavior. The present review summarizes work from clinical and preclinical populations on sex differences in drug use and abuse, ranging from initiation to escalation/dysregulation and from drug cessation/abstinence to relapse. These differences are analyzed in the context of the addiction cycle conceptualization of Koob and his colleagues and address patterns of drug use (binge/intoxication), motivation underlying its use (withdrawal/negative affect) and likelihood and causes of craving and relapse of drug taking (preoccupation/anticipation). Following this overview, an assessment of the basis for the reported sex differences is discussed in the context of the affective (rewarding and aversive) properties of drugs of abuse and how such properties and their balance vary with sex and contribute to drug intake. Finally, the interaction of sex with several experiential (drug history) and subject (age) factors and how these interactions affect reward and aversion are discussed to highlight the importance of understanding such interactions in predicting drug use and abuse. We note that sex as a biological variable remains one of critical evaluation and that such investigations of sex differences in drug use and abuse continue and be expanded to assess all facets of their mediation, including these affective properties, how their balance may be impacted by the multiple conditions under which drugs are taken and how this overall balance affects drug use and addiction vulnerability.
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Affiliation(s)
- Anthony L Riley
- Psychopharmacology Laboratory, Center for Behavioral Neuroscience, American University, 4400 Massachusetts Ave, NW, Washington, D.C. 20016, USA.
| | - Briana J Hempel
- Psychopharmacology Laboratory, Center for Behavioral Neuroscience, American University, 4400 Massachusetts Ave, NW, Washington, D.C. 20016, USA
| | - Matthew M Clasen
- Psychopharmacology Laboratory, Center for Behavioral Neuroscience, American University, 4400 Massachusetts Ave, NW, Washington, D.C. 20016, USA
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Sheth C, Furlong TM, Keefe KA, Taha SA. The lateral hypothalamus to lateral habenula projection, but not the ventral pallidum to lateral habenula projection, regulates voluntary ethanol consumption. Behav Brain Res 2017; 328:195-208. [PMID: 28432009 PMCID: PMC5500222 DOI: 10.1016/j.bbr.2017.04.029] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 03/23/2017] [Accepted: 04/17/2017] [Indexed: 11/26/2022]
Abstract
The lateral habenula (LHb) is an epithalamic brain region implicated in aversive processing via negative modulation of midbrain dopamine (DA) and serotonin (5-HT) systems. Given the role of the LHb in inhibiting DA and 5-HT systems, it is thought to be involved in various psychiatric pathologies, including drug addiction. In support, it has been shown that LHb plays a critical role in cocaine- and ethanol-related behaviors, most likely by mediating drug-induced aversive conditioning. In our previous work, we showed that LHb lesions increased voluntary ethanol consumption and operant ethanol self-administration and blocked yohimbine-induced reinstatement of ethanol self-administration. LHb lesions also attenuated ethanol-induced conditioned taste aversion suggesting that a mechanism for the increased intake of ethanol may be reduced aversion learning. However, whether afferents to the LHb are required for mediating effects of the LHb on these behaviors remained to be investigated. Our present results show that lesioning the fiber bundle carrying afferent inputs to the LHb, the stria medullaris (SM), increases voluntary ethanol consumption, suggesting that afferent structures projecting to the LHb are important for mediating ethanol-directed behaviors. We then chose two afferent structures as the focus of our investigation. We specifically studied the role of the inputs from the lateral hypothalamus (LH) and ventral pallidum (VP) to the LHb in ethanol-directed behaviors. Our results show that the LH-LHb projection is necessary for regulating voluntary ethanol consumption. These results are an important first step towards understanding the functional role of afferents to LHb with regard to ethanol consumption.
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Affiliation(s)
- Chandni Sheth
- Department of Pharmacology and Toxicology, University of Utah, 30 South 2000 East, Salt Lake City, UT 84112-5820, USA.
| | - Teri M Furlong
- Department of Pharmacology and Toxicology, University of Utah, 30 South 2000 East, Salt Lake City, UT 84112-5820, USA
| | - Kristen A Keefe
- Department of Pharmacology and Toxicology, University of Utah, 30 South 2000 East, Salt Lake City, UT 84112-5820, USA
| | - Sharif A Taha
- Department of Pharmacology and Toxicology, University of Utah, 30 South 2000 East, Salt Lake City, UT 84112-5820, USA
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Abstract
Learning what to eat and what not to eat is fundamental to our well-being, quality of life, and survival. In particular, the acquisition of conditioned taste aversions (CTAs) protects all animals (including humans) against ingesting foods that contain poisons or toxins. Counterintuitively, CTAs can also develop in situations in which we know with absolute certainty that the food did not cause the subsequent aversive systemic effect. Recent nonhuman animal research, analyzing palatability shifts, has indicated that a wider range of stimuli than has been traditionally acknowledged can induce CTAs. This article integrates these new findings with a reappraisal of some known characteristics of CTA and presents a novel conceptual analysis that is broader and more comprehensive than previous accounts of CTA learning.
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Affiliation(s)
- Jian-You Lin
- Department of Psychology, University of Illinois at Chicago, 1007 West Harrison Street, Chicago, IL, 60607, USA.
| | - Joe Arthurs
- Department of Psychology, University of Illinois at Chicago, 1007 West Harrison Street, Chicago, IL, 60607, USA
| | - Steve Reilly
- Department of Psychology, University of Illinois at Chicago, 1007 West Harrison Street, Chicago, IL, 60607, USA.
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Zuo W, Fu R, Hopf FW, Xie G, Krnjević K, Li J, Ye JH. Ethanol drives aversive conditioning through dopamine 1 receptor and glutamate receptor-mediated activation of lateral habenula neurons. Addict Biol 2017; 22:103-116. [PMID: 26283508 DOI: 10.1111/adb.12298] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 07/15/2015] [Accepted: 07/23/2015] [Indexed: 12/11/2022]
Abstract
There has been increasing interest in the lateral habenula (LHb) given its potent regulatory role in many aversion-related behaviors. Interestingly, ethanol can be rewarding as well as aversive; we therefore investigated whether ethanol exposure alters pacemaker firing or glutamate receptor signaling in LHb neurons in vitro and also whether LHb activity in vivo might contribute to the acquisition of conditioned place aversion to ethanol. Surprisingly, in epithalamic slices, low doses of ethanol (1.4 mM) strongly accelerated LHb neuron firing (by ~60%), and ethanol's effects were much reduced by blocking glutamate receptors. Ethanol increased presynaptic glutamate release, and about half of this effect was mediated by dopamine subtype 1 receptors (D1Rs) and cyclic adenosine monophosphate (cAMP)-dependent signaling pathways. In agreement with these findings, c-Fos immunoreactivity in LHb regions was enhanced after a single administration of a low dose of ethanol (0.25 g/kg i.p.). Importantly, the same dose of ethanol in vivo also produced strong conditioned place aversion, and this was prevented by inhibiting D1Rs or neuronal activity within the LHb. By contrast, a higher dose (2 g/kg) led to ethanol conditioned place preference, which was enhanced by inhibiting neuronal activity or D1Rs within the LHb and suppressed by infusing aminomethylphosphonic acid or the D1R agonist SKF38393 within the LHb. Our in vitro and in vivo observations show, for the first time, that ethanol increases LHb excitation, mediated by D1R and glutamate receptors, and may underlie a LHb aversive signal that contributes to ethanol-related aversion.
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Affiliation(s)
- Wanhong Zuo
- Department of Anesthesiology, Pharmacology and Physiology, New Jersey Medical School; Rutgers, The State University of New Jersey; Newark NJ USA
| | - Rao Fu
- Department of Anesthesiology, Pharmacology and Physiology, New Jersey Medical School; Rutgers, The State University of New Jersey; Newark NJ USA
| | - Frederic Woodward Hopf
- Department of Neurology; University of California at San Francisco; San Francisco CA USA
| | - Guiqin Xie
- Department of Anesthesiology, Pharmacology and Physiology, New Jersey Medical School; Rutgers, The State University of New Jersey; Newark NJ USA
| | | | - Jing Li
- Department of Anesthesiology, Pharmacology and Physiology, New Jersey Medical School; Rutgers, The State University of New Jersey; Newark NJ USA
| | - Jiang-Hong Ye
- Department of Anesthesiology, Pharmacology and Physiology, New Jersey Medical School; Rutgers, The State University of New Jersey; Newark NJ USA
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Tandon S, Keefe KA, Taha SA. Excitation of lateral habenula neurons as a neural mechanism underlying ethanol-induced conditioned taste aversion. J Physiol 2016; 595:1393-1412. [PMID: 27682823 DOI: 10.1113/jp272994] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 09/23/2016] [Indexed: 12/23/2022] Open
Abstract
KEY POINTS The lateral habenula (LHb) has been implicated in regulation of drug-seeking behaviours through aversion-mediated learning. In this study, we recorded neuronal activity in the LHb of rats during an operant task before and after ethanol-induced conditioned taste aversion (CTA) to saccharin. Ethanol-induced CTA caused significantly higher baseline firing rates in LHb neurons, as well as elevated firing rates in response to cue presentation, lever press and saccharin taste. In a separate cohort of rats, we found that bilateral LHb lesions blocked ethanol-induced CTA. Our results strongly suggest that excitation of LHb neurons is required for ethanol-induced CTA, and point towards a mechanism through which LHb firing may regulate voluntary ethanol consumption. ABSTRACT Ethanol, like other drugs of abuse, has both rewarding and aversive properties. Previous work suggests that sensitivity to ethanol's aversive effects negatively modulates voluntary alcohol intake and thus may be important in vulnerability to developing alcohol use disorders. We previously found that rats with lesions of the lateral habenula (LHb), which is implicated in aversion-mediated learning, show accelerated escalation of voluntary ethanol consumption. To understand neural encoding in the LHb contributing to ethanol-induced aversion, we recorded neural firing in the LHb of freely behaving, water-deprived rats before and after an ethanol-induced (1.5 g kg-1 20% ethanol, i.p.) conditioned taste aversion (CTA) to saccharin taste. Ethanol-induced CTA strongly decreased motivation for saccharin in an operant task to obtain the tastant. Comparison of LHb neural firing before and after CTA induction revealed four main differences in firing properties. First, baseline firing after CTA induction was significantly higher. Second, firing evoked by cues signalling saccharin availability shifted from a pattern of primarily inhibition before CTA to primarily excitation after CTA induction. Third, CTA induction reduced the magnitude of lever press-evoked inhibition. Finally, firing rates were significantly higher during consumption of the devalued saccharin solution after CTA induction. Next, we studied sham- and LHb-lesioned rats in our operant CTA paradigm and found that LHb lesion significantly attenuated CTA effects in the operant task. Our data demonstrate the importance of LHb excitation in regulating expression of ethanol-induced aversion and suggest a mechanism for its role in modulating escalation of voluntary ethanol intake.
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Affiliation(s)
- Shashank Tandon
- Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, 84112-5820, USA
| | - Kristen A Keefe
- Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, 84112-5820, USA
| | - Sharif A Taha
- Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, 84112-5820, USA
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Drgonova J, Walther D, Hartstein GL, Bukhari MO, Baumann MH, Katz J, Hall FS, Arnold ER, Flax S, Riley A, Rivero-Martin O, Lesch KP, Troncoso J, Ranscht B, Uhl GR. Cadherin 13: human cis-regulation and selectively-altered addiction phenotypes and cerebral cortical dopamine in knockout mice. Mol Med 2016; 22:537-547. [PMID: 27579475 PMCID: PMC5082297 DOI: 10.2119/molmed.2015.00170] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 07/29/2016] [Indexed: 12/22/2022] Open
Abstract
The cadherin 13 (CDH13) gene encodes a cell adhesion molecule likely to influence development and connections of brain circuits that modulate addiction, locomotion and cognition, including those that involve midbrain dopamine neurons. Human CDH13 mRNA expression differs by more than 80% in postmortem cerebral cortical samples from individuals with different CDH13 genotypes, supporting examination of mice with altered Cdh13 expression as models for common human variation at this locus. Constitutive cdh13 knockout mice display evidence for changed cocaine reward: shifted dose response relationship in tests of cocaine-conditioned place preference using doses that do not alter cocaine conditioned taste aversion. Reduced adult Cdh13 expression in conditional knockouts also alters cocaine reward in ways that correlate with individual differences in cortical Cdh13 mRNA levels. In control and comparison behavioral assessments, knockout mice display modestly-quicker acquisition of rotarod and water maze tasks, with a trend toward faster acquisition of 5 choice serial reaction time tasks that otherwise displayed no genotype-related differences. They display significant differences in locomotion in some settings, with larger effects in males. In assessments of brain changes that might contribute to these behavioral differences, there are selective alterations of dopamine levels, dopamine/metabolite ratios, dopaminergic fiber densities and mRNA encoding the activity dependent transcription factor npas4 in cerebral cortex of knockout mice. These novel data and previously reported human associations of CDH13 variants with addiction, individual differences in responses to stimulant administration and attention deficit hyperactivity disorder (ADHD) phenotypes suggest that levels of CDH13 expression, through mechanisms likely to include effects on mesocortical dopamine, influence stimulant reward and may contribute modestly to cognitive and locomotor phenotypes relevant to ADHD.
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Affiliation(s)
- Jana Drgonova
- Molecular Neurobiology, NIH-IRP, NIDA, Baltimore, Maryland 21224
| | - Donna Walther
- Molecular Neurobiology, NIH-IRP, NIDA, Baltimore, Maryland 21224
| | - G Luke Hartstein
- Molecular Neurobiology, NIH-IRP, NIDA, Baltimore, Maryland 21224
| | | | | | - Jonathan Katz
- Medicinal Chemistry, NIH-IRP, NIDA, Baltimore, Maryland 21224
| | - Frank Scott Hall
- Molecular Neurobiology, NIH-IRP, NIDA, Baltimore, Maryland 21224
| | | | - Shaun Flax
- Dept of Psychology, American Univ, Washington, DC
| | | | - Olga Rivero-Martin
- Translational Neurobiology, Dept Psychiatry, Univ Würzburg, Würzburg Germany
| | - Klaus-Peter Lesch
- Translational Neurobiology, Dept Psychiatry, Univ Würzburg, Würzburg Germany
| | - Juan Troncoso
- Div Neuropathology, Johns Hopkins Sch Med, Baltimore MD 21202
| | | | - George R Uhl
- Molecular Neurobiology, NIH-IRP, NIDA, Baltimore, Maryland 21224
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Fu R, Zuo W, Gregor D, Li J, Grech D, Ye JH. Pharmacological Manipulation of the Rostromedial Tegmental Nucleus Changes Voluntary and Operant Ethanol Self-Administration in Rats. Alcohol Clin Exp Res 2016; 40:572-82. [PMID: 26876382 PMCID: PMC4775316 DOI: 10.1111/acer.12974] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 11/23/2015] [Indexed: 01/07/2023]
Abstract
BACKGROUND The aversive properties of ethanol (EtOH) that limit its intake are poorly understood. There is an increasing interest in the role of the rostromedial tegmental nucleus (RMTg), because it encodes aversion signals and inhibits motivated behaviors. It is also a major source of inhibitory GABAergic inputs to the midbrain dopamine neurons. Up to this time, the role of the RMTg in EtOH-drinking behaviors has not been well explored. METHODS Male Long-Evans rats were trained either to drink EtOH under the intermittent 2-bottle-choice protocol or to self-administer EtOH in operant chambers under fixed-ratio-3 schedules. Changes in drinking behaviors induced by the bilateral infusion into the RMTg of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), an agonist of AMPA-type glutamate receptors, or muscimol, an agonist of GABAA receptors, were measured. RESULTS Consumption and preference for EtOH, numbers of active lever pressing, and head entrance to the EtOH port were all significantly decreased upon activation of the RMTg by the infusion of AMPA, but were increased upon inhibition of the RMTg by the infusion of muscimol. By contrast, intra-RMTg infusion of these agents did not change sucrose consumption. CONCLUSIONS These data show for the first time that EtOH-drinking and EtOH-seeking behaviors of rats changed inversely with RMTg function, supporting the idea that the RMTg plays a crucial role in EtOH-drinking behaviors.
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Affiliation(s)
- Rao Fu
- Department of Anesthesiology, Pharmacology and Physiology, Rutgers, The State University of New Jersey, New Jersey Medical School, Newark, New Jersey, USA
| | - Wanhong Zuo
- Department of Anesthesiology, Pharmacology and Physiology, Rutgers, The State University of New Jersey, New Jersey Medical School, Newark, New Jersey, USA
| | - Danielle Gregor
- Department of Anesthesiology, Pharmacology and Physiology, Rutgers, The State University of New Jersey, New Jersey Medical School, Newark, New Jersey, USA
| | - Jing Li
- Department of Anesthesiology, Pharmacology and Physiology, Rutgers, The State University of New Jersey, New Jersey Medical School, Newark, New Jersey, USA
| | - Dennis Grech
- Department of Anesthesiology, Pharmacology and Physiology, Rutgers, The State University of New Jersey, New Jersey Medical School, Newark, New Jersey, USA
| | - Jiang-Hong Ye
- Department of Anesthesiology, Pharmacology and Physiology, Rutgers, The State University of New Jersey, New Jersey Medical School, Newark, New Jersey, USA
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Delta-9-tetrahydrocannabinol (THC) history fails to affect THC's ability to induce place preferences in rats. Pharmacol Biochem Behav 2016; 144:1-6. [PMID: 26905371 DOI: 10.1016/j.pbb.2016.02.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 02/17/2016] [Indexed: 01/07/2023]
Abstract
RATIONALE In pre-clinical models of marijuana abuse, there is relatively limited evidence of delta-9-tetrahydrocannabinol's (THC) rewarding effects, as indexed by its general inability to induce a place preference. One explanation for this failure is that its rewarding effects are masked by its concurrently occurring aversive properties. Consistent with this explanation, THC pre-exposure, which presumably weakens its aversive effects, induces place preferences. Such demonstrations are limited to mice and given reported species differences in THC reactivity, it is unknown to what extent the same shift in affective properties would be evident in rats. METHODS The present experiment examined the effect of THC history (3.2mg/kg) on THC (1 or 3.2mg/kg) induced place preference conditioning in rats. An assessment of taste avoidance was also run to independently characterize THC's aversive effects and any changes that occurred with drug pre-exposure. These assessments were made in a combined taste avoidance/place preference procedure in which a novel saccharin solution and environment were paired with THC (0, 1 or 3.2mg/kg). RESULTS THC did not induce place conditioning, and a history of THC was ineffective in increasing THC's ability to do so, despite the fact that this same history significantly attenuated the aversive effects of THC. CONCLUSIONS The failure of THC to consistently induce place preferences has been argued to be a function of its concurrently occurring aversive effects masking its rewarding properties. The fact that pre-exposure to THC significantly reduced its aversive effects without impacting THC's ability to induce place preferences suggests that THC has weak rewarding effects and/or its residual aversive affects may have still masked its rewarding properties. An important area for future work will be characterizing under what conditions THC is rewarding and whether its overall reinforcing effects are impacted by the relationship between its affective properties.
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Sheth C, Furlong TM, Keefe KA, Taha SA. Lesion of the rostromedial tegmental nucleus increases voluntary ethanol consumption and accelerates extinction of ethanol-induced conditioned taste aversion. Psychopharmacology (Berl) 2016; 233:3737-3749. [PMID: 27549757 PMCID: PMC5063894 DOI: 10.1007/s00213-016-4406-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 08/07/2016] [Indexed: 01/06/2023]
Abstract
RATIONALE Ethanol has rewarding and aversive properties, and the balance of these properties influences voluntary ethanol consumption. Preclinical and clinical evidence show that the aversive properties of ethanol limit intake. The neural circuits underlying ethanol-induced aversion learning are not fully understood. We have previously shown that the lateral habenula (LHb), a region critical for aversive conditioning, plays an important role in ethanol-directed behaviors. However, the neurocircuitry through which LHb exerts its actions is unknown. OBJECTIVE In the present study, we investigate a role for the rostromedial tegmental nucleus (RMTg), a major LHb projection target, in regulating ethanol-directed behaviors. METHODS Rats received either sham or RMTg lesions and were studied during voluntary ethanol consumption; operant ethanol self-administration, extinction, and yohimbine-induced reinstatement of ethanol-seeking; and ethanol-induced conditioned taste aversion (CTA). RESULTS RMTg lesions increased voluntary ethanol consumption and accelerated extinction of ethanol-induced CTA. CONCLUSIONS The RMTg plays an important role in regulating voluntary ethanol consumption, possibly by mediating ethanol-induced aversive conditioning.
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Affiliation(s)
- Chandni Sheth
- Department of Pharmacology and Toxicology, University of Utah, 30 South 2000 East, Salt Lake City, UT, 84112-5820, USA.
| | - Teri M. Furlong
- Department of Pharmacology and Toxicology, University of Utah, 30 South 2000 East, Salt Lake City, UT 84112-5820 USA
| | - Kristen A. Keefe
- Department of Pharmacology and Toxicology, University of Utah, 30 South 2000 East, Salt Lake City, UT 84112-5820 USA
| | - Sharif A. Taha
- Department of Pharmacology and Toxicology, University of Utah, 30 South 2000 East, Salt Lake City, UT 84112-5820 USA
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Pelloux Y, Costentin J, Duterte-Boucher D. Differential involvement of anxiety and novelty preference levels on oral ethanol consumption in rats. Psychopharmacology (Berl) 2015; 232:2711-21. [PMID: 25761842 DOI: 10.1007/s00213-015-3910-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 02/23/2015] [Indexed: 11/24/2022]
Abstract
RATIONALE Drug addiction is defined as a recurring cycle of intoxication, abstinence and relapse. The behavioural trait of novelty seeking is frequently observed in alcohol abusers. Moreover, converging evidence indicates that anxious individuals are also predisposed to alcohol abuse. OBJECTIVES We have analyzed the respective implication of those two behavioural factors on vulnerability to ethanol intake on rats in situations designed to reflect drug intoxication and relapse phases in humans. METHODS In a general population of Wistar rats, animals were tested in both the light/dark box and the novelty preference tests. Ethanol consumption was measured in a two-bottle free-choice procedure across three successive procedures. Animals were first exposed to increasing concentrations of ethanol (2, 4, 6, 8, 10, 12 % for 8 days at each concentration). Then, the concentration of the solution was diminished from 12 to 6 %. Finally, all rats were re-exposed to 6 % ethanol after 12 days of ethanol deprivation. RESULTS Novelty preference predicted the amount of ethanol consumed across all phases. In contrast, anxiety was associated with a quicker recovery of ethanol consumption after the concentration drop and a greater increase in ethanol consumption after deprivation. CONCLUSIONS Novelty seeking and anxiety are both but differentially implicated in predisposition to ethanol abuse. Whereas novelty seeking is related to the amount of ethanol consumed, anxiety is associated to higher ethanol consumption when ethanol concentration is decreased or after ethanol deprivation.
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Affiliation(s)
- Yann Pelloux
- Unité de Neuropsychopharmacologie Expérimentale, EA 4359, Institut de Recherche et d'Innovation Biomédicale (IRIB), Faculté de Médecine et de Pharmacie de Rouen, 22, Bld Gambetta, 76183, Rouen Cedex, France
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Harris AC, Tally L, Muelken P, Banal A, Schmidt CE, Cao Q, LeSage MG. Effects of nicotine and minor tobacco alkaloids on intracranial-self-stimulation in rats. Drug Alcohol Depend 2015; 153:330-4. [PMID: 26094184 PMCID: PMC4509975 DOI: 10.1016/j.drugalcdep.2015.06.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 06/01/2015] [Accepted: 06/02/2015] [Indexed: 12/22/2022]
Abstract
BACKGROUND While nicotine is the primary addictive compound in tobacco, other tobacco constituents including minor alkaloids (e.g., nornicotine, anabasine) may also contribute to tobacco addiction by mimicking or enhancing the effects of nicotine. Further evaluating the behavioral effects of minor alkaloids is essential for understanding their impact on tobacco addiction and informing development of tobacco product standards by the FDA. METHODS This study compared the addiction-related effects of nicotine and the minor alkaloids nornicotine, anabasine, myosmine, anatabine, and cotinine on intracranial self-stimulation (ICSS) thresholds in rats. RESULTS Acute injection of nicotine produced reinforcement-enhancing (ICSS threshold-decreasing) effects at low to moderate doses, and reinforcement-attenuating/aversive (ICSS threshold-increasing) effects at high doses. Nornicotine and anabasine produced similar biphasic effects on ICSS thresholds, although with lower potency compared to nicotine. Myosmine only elevated ICSS thresholds at relatively high doses, while anatabine and cotinine did not influence ICSS thresholds at any dose. None of the alkaloids significantly influenced ICSS response latencies, indicating a lack of nonspecific motoric effects. CONCLUSIONS These findings indicate that some minor tobacco alkaloids can either fully (nornicotine, anabasine) or partially (myosmine) mimic nicotine's addiction-related effects on ICSS, albeit at reduced potency. These findings emphasize the need for further study of the abuse potential of minor alkaloids, including evaluation of their effects when combined with nicotine and other tobacco constituents to better simulate tobacco exposure in humans. Such work is essential for informing FDA regulation of tobacco products and could also lead to the development of novel pharmacotherapies for tobacco addiction.
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Affiliation(s)
- Andrew C. Harris
- Minneapolis Medical Research Foundation, Minneapolis, MN,Department of Medicine, University of Minnesota Medical School, Minneapolis, MN,Department of Psychology, University of Minnesota, Minneapolis, MN
| | - Laura Tally
- Minneapolis Medical Research Foundation, Minneapolis, MN
| | - Peter Muelken
- Minneapolis Medical Research Foundation, Minneapolis, MN,Department of Ecology, Evolution, and Behavior, University of Minnesota, Minneapolis, MN
| | - Andrew Banal
- Minneapolis Medical Research Foundation, Minneapolis, MN,Department of Psychology, University of Minnesota, Minneapolis, MN
| | - Clare E. Schmidt
- Minneapolis Medical Research Foundation, Minneapolis, MN,Department of Neuroscience, University of Minnesota, Minneapolis, MN
| | - Qing Cao
- Masonic Cancer Center Biostatistics and Bioinformatics Core, University of Minnesota, Minneapolis, MN
| | - Mark G. LeSage
- Minneapolis Medical Research Foundation, Minneapolis, MN,Department of Medicine, University of Minnesota Medical School, Minneapolis, MN,Department of Psychology, University of Minnesota, Minneapolis, MN
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Sex differences in the long-lasting consequences of adolescent ethanol exposure for the rewarding effects of cocaine in mice. Psychopharmacology (Berl) 2015; 232:2995-3007. [PMID: 25943165 DOI: 10.1007/s00213-015-3937-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 04/07/2015] [Indexed: 01/01/2023]
Abstract
RATIONALE The practice of binge drinking is very common among adolescents of both sexes. It can have long-term consequences with respect to drug consumption during adulthood, but knowledge on these effects in females is limited. OBJECTIVES The long-lasting effects of intermittent exposure to ethanol (EtOH) during adolescence on different cocaine-elicited behaviours, including locomotor reactivity, conditioned place preference (CPP) and intravenous self-administration, were evaluated in male and female adult mice. It was hypothesized that an EtOH binge during adolescence would increase sensitivity to the effects of a sub-threshold dose of cocaine and has a differential impact on the drug's effects in males and females. METHODS Adolescent OF1 mice (postnatal day (PND) 26) underwent a 2-week pre-treatment schedule consisting of 16 doses of EtOH (2.5 g/kg) or saline (twice daily administrations separated by a 4-h interval i.p.) administered on two consecutive days separated by an interval of 2 days. Three weeks later (PND > 60), we assessed locomotor activity responses induced by an acute injection of different doses of cocaine in experiment 1 and the rewarding effects of cocaine on the CPP (1 mg/kg) and intravenous self-administration (1 mg/kg/infusion) paradigms in experiment 2. RESULTS Pre-exposure to EtOH during adolescence altered motor reactivity to cocaine in a dose- and sex-dependent manner, increased sensitivity to cocaine in CPP and enhanced self-administration in adult mice. CONCLUSIONS The effects of intermittent exposure to ethanol during adolescence are evident in adulthood, during which greater sensitivity and intake of cocaine is observed and differ in each sex.
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King HE, Wakeford A, Taylor W, Wetzell B, Rice KC, Riley AL. Sex differences in 3,4-methylenedioxypyrovalerone (MDPV)-induced taste avoidance and place preferences. Pharmacol Biochem Behav 2015. [PMID: 26216834 DOI: 10.1016/j.pbb.2015.07.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Synthetic cathinones, otherwise known as "bath salts", have gained significant attention in the last few years as a result of increased use and abuse. One such compound, 3,4-methylenedioxypyrovalerone (MDPV), is pharmacologically and behaviorally similar to cocaine and has been shown to possess both aversive and rewarding effects. For a host of other drugs, each of these effects (and their relative balance) can be influenced by a variety of factors, including sex, which in turn impacts drug taking behavior. In this context, the present assessment sought to determine whether males and females differed in MDPV-induced CTA and CPP. Both male and female Sprague-Dawley rats underwent a combined CTA/CPP procedure, in which an injection of one of three doses of MDPV (1.0, 1.8 or 3.2mg/kg) was paired with both a novel saccharin solution and a novel environment and changes in preferences for these stimuli were examined. Taste avoidance was evident in both sexes, although this avoidance was weaker in females compared to males. MDPV also produced place preferences in all drug-treated animals, but these preferences did not vary as a function of sex. The fact that females showed a weaker avoidance response compared to males (despite comparable preferences) suggests that females may have a heightened susceptibility to use and abuse of MDPV, paralleling results seen with cocaine and other stimulants. The present findings extend the behavioral characterization of MDPV and the factors that may alter its aversive and rewarding effects.
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Affiliation(s)
- Heather E King
- Psychopharmacology Laboratory, Department of Psychology, American University, Washington, DC 20016, United States.
| | - Alison Wakeford
- Psychopharmacology Laboratory, Department of Psychology, American University, Washington, DC 20016, United States
| | - William Taylor
- Psychopharmacology Laboratory, Department of Psychology, American University, Washington, DC 20016, United States
| | - Bradley Wetzell
- Psychopharmacology Laboratory, Department of Psychology, American University, Washington, DC 20016, United States
| | - Kenner C Rice
- Chemical Biology Research Branch, National Institute on Drug Abuse, Bethesda, MD 20892, United States
| | - Anthony L Riley
- Psychopharmacology Laboratory, Department of Psychology, American University, Washington, DC 20016, United States
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Gore-Langton JK, Flax SM, Pomfrey RL, Wetzell BB, Riley AL. Measures of the aversive effects of drugs: A comparison of conditioned taste and place aversions. Pharmacol Biochem Behav 2015; 134:99-105. [DOI: 10.1016/j.pbb.2015.05.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 04/30/2015] [Accepted: 05/04/2015] [Indexed: 01/07/2023]
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Legastelois R, Darcq E, Wegner SA, Lombroso PJ, Ron D. Striatal-enriched protein tyrosine phosphatase controls responses to aversive stimuli: implication for ethanol drinking. PLoS One 2015; 10:e0127408. [PMID: 25992601 PMCID: PMC4438985 DOI: 10.1371/journal.pone.0127408] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 04/15/2015] [Indexed: 11/18/2022] Open
Abstract
The STriatal-Enriched protein tyrosine Phosphatase (STEP) is a brain-specific phosphatase whose dysregulation in expression and/or activity is associated with several neuropsychiatric disorders. We recently showed that long-term excessive consumption of ethanol induces a sustained inhibition of STEP activity in the dorsomedial striatum (DMS) of mice. We further showed that down-regulation of STEP expression in the DMS, and not in the adjacent dorsolateral striatum, increases ethanol intake, suggesting that the inactivation of STEP in the DMS contributes to the development of ethanol drinking behaviors. Here, we compared the consequence of global deletion of the STEP gene on voluntary ethanol intake to the consumption of an appetitive rewarding substance (saccharin) or an aversive solution (quinine or denatonium). Whereas saccharin intake was similar in STEP knockout (KO) and wild type (WT) littermate mice, the consumption of ethanol as well as quinine and denatonium was increased in STEP KO mice. These results suggested that the aversive taste of these substances was masked upon deletion of the STEP gene. We therefore hypothesized that STEP contributes to the physiological avoidance towards aversive stimuli. To further test this hypothesis, we measured the responses of STEP KO and WT mice to lithium-induced conditioned place aversion (CPA) and found that whereas WT mice developed lithium place aversion, STEP KO mice did not. In contrast, conditioned place preference (CPP) to ethanol was similar in both genotypes. Together, our results indicate that STEP contributes, at least in part, to the protection against the ingestion of aversive agents.
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Affiliation(s)
- Rémi Legastelois
- Department of Neurology, University of California San Francisco, San Francisco, California, United States of America
| | - Emmanuel Darcq
- Department of Neurology, University of California San Francisco, San Francisco, California, United States of America
| | - Scott A. Wegner
- Department of Neurology, University of California San Francisco, San Francisco, California, United States of America
| | - Paul J. Lombroso
- Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Dorit Ron
- Department of Neurology, University of California San Francisco, San Francisco, California, United States of America
- * E-mail:
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King HE, Wetzell B, Rice KC, Riley AL. An assessment of MDPV-induced place preference in adult Sprague-Dawley rats. Drug Alcohol Depend 2015; 146:116-9. [PMID: 25468817 PMCID: PMC5551401 DOI: 10.1016/j.drugalcdep.2014.11.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 11/03/2014] [Accepted: 11/04/2014] [Indexed: 12/18/2022]
Abstract
OBJECTIVE Most drugs of abuse have both aversive and rewarding effects, and the use and abuse potential of such drugs is thought to be a function of a balance of these affective properties. Characterizing these effects and their relative balance may provide insight into abuse vulnerability. One drug that has received recent attention is methylenedioxypyrovalerone (MDPV), a monoamine transport inhibitor similar to, but significantly more potent than, cocaine. MDPV is self-administered and has been shown to produce aversive and rewarding effects in adult rats. The present study extended this characterization of the affective properties of MDPV by examining its ability to support place conditioning at a range of doses known to produce taste avoidance. METHODS Male Sprague-Dawley rats were injected with MDPV (1, 1.8 or 3.2mg/kg) or saline and placed on the non-preferred side of a place conditioning apparatus for 30 min. On the next day, they were given an injection of saline and placed on the preferred side. This was repeated three times for a total of four conditioning cycles, and side preference was assessed on a final test. RESULTS All doses of MDPV produced significant increases in time spent in the drug-paired chamber, an effect not seen in vehicle-treated animals. CONCLUSIONS That the same doses of MDPV induced both taste avoidance and place preference allows assessments of how other factors might impact these effects and how they may, in turn, contribute to its abuse liability.
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Affiliation(s)
- Heather E. King
- Psychopharmacology Laboratory, Department of Psychology, American University, Washington, DC 20016
| | - Bradley Wetzell
- Psychopharmacology Laboratory, Department of Psychology, American University, Washington, DC 20016
| | - Kenner C. Rice
- Chemical Biology Research Branch, National Institute on Drug Abuse, Bethesda, MD 20892
| | - Anthony L. Riley
- Psychopharmacology Laboratory, Department of Psychology, American University, Washington, DC 20016
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Conditioned taste aversion, drugs of abuse and palatability. Neurosci Biobehav Rev 2014; 45:28-45. [PMID: 24813806 DOI: 10.1016/j.neubiorev.2014.05.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2013] [Revised: 04/15/2014] [Accepted: 05/01/2014] [Indexed: 11/23/2022]
Abstract
We consider conditioned taste aversion to involve a learned reduction in the palatability of a taste (and hence in amount consumed) based on the association that develops when a taste experience is followed by gastrointestinal malaise. The present article evaluates the well-established finding that drugs of abuse, at doses that are otherwise considered rewarding and self-administered, cause intake suppression. Our recent work using lick pattern analysis shows that drugs of abuse also cause a palatability downshift and, therefore, support conditioned taste aversion learning.
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Haack AK, Sheth C, Schwager AL, Sinclair MS, Tandon S, Taha SA. Lesions of the lateral habenula increase voluntary ethanol consumption and operant self-administration, block yohimbine-induced reinstatement of ethanol seeking, and attenuate ethanol-induced conditioned taste aversion. PLoS One 2014; 9:e92701. [PMID: 24695107 PMCID: PMC3973636 DOI: 10.1371/journal.pone.0092701] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 02/25/2014] [Indexed: 11/19/2022] Open
Abstract
The lateral habenula (LHb) plays an important role in learning driven by negative outcomes. Many drugs of abuse, including ethanol, have dose-dependent aversive effects that act to limit intake of the drug. However, the role of the LHb in regulating ethanol intake is unknown. In the present study, we compared voluntary ethanol consumption and self-administration, yohimbine-induced reinstatement of ethanol seeking, and ethanol-induced conditioned taste aversion in rats with sham or LHb lesions. In rats given home cage access to 20% ethanol in an intermittent access two bottle choice paradigm, lesioned animals escalated their voluntary ethanol consumption more rapidly than sham-lesioned control animals and maintained higher stable rates of voluntary ethanol intake. Similarly, lesioned animals exhibited higher rates of responding for ethanol in operant self-administration sessions. In addition, LHb lesion blocked yohimbine-induced reinstatement of ethanol seeking after extinction. Finally, LHb lesion significantly attenuated an ethanol-induced conditioned taste aversion. Our results demonstrate an important role for the LHb in multiple facets of ethanol-directed behavior, and further suggest that the LHb may contribute to ethanol-directed behaviors by mediating learning driven by the aversive effects of the drug.
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Affiliation(s)
- Andrew K. Haack
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Interdepartmental Program in Neuroscience, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Chandni Sheth
- Department of Pharmacology and Toxicology, University of Utah School of Medicine, United States Salt Lake City, Utah, United States of America
| | - Andrea L. Schwager
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Interdepartmental Program in Neuroscience, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Michael S. Sinclair
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Shashank Tandon
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Sharif A. Taha
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Interdepartmental Program in Neuroscience, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- * E-mail:
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