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Peart DR, Nolan CJ, Stone AP, Williams MA, Karlovcec JM, Murray JE. Disruption of positive- and negative-feature morphine interoceptive occasion setters by dopamine receptor agonism and antagonism in male and female rats. Psychopharmacology (Berl) 2024; 241:1597-1615. [PMID: 38580732 DOI: 10.1007/s00213-024-06584-y] [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: 07/16/2023] [Accepted: 03/29/2024] [Indexed: 04/07/2024]
Abstract
RATIONALE Internally perceived stimuli evoked by morphine administration can form Pavlovian associations such that they can function as occasion setters (OSs) for externally perceived reward cues in rats, coming to modulate reward-seeking behaviour. Though much research has investigated mechanisms underlying opioid-related reinforcement and analgesia, neurotransmitter systems involved in the functioning of opioids as Pavlovian interoceptive discriminative stimuli remain to be disentangled despite documented differences in the development of tolerance to analgesic versus discriminative stimulus effects. OBJECTIVES Dopamine has been implicated in many opioid-related behaviours, so we aimed to investigate the role of this neurotransmitter in expression of morphine occasion setting. METHODS Male and female rats were assigned to positive- (FP) or negative-feature (FN) groups and received an injection of morphine or saline before each training session. A 15-s white noise conditioned stimulus (CS) was presented 8 times during every training session; offset of this stimulus was followed by 4-s access to liquid sucrose on morphine, but not saline, sessions for FP rats. FN rats learned the reverse contingency. Following stable discrimination, rats began generalization testing for expression of morphine-guided sucrose seeking after systemic pretreatment with different doses of the non-selective dopamine receptor antagonist, flupenthixol, and the non-selective dopamine receptor agonist, apomorphine, combined with training doses of morphine or saline in a Latin-square design. RESULTS The morphine discrimination was acquired under both FP and FN contingencies by males and females. Neither flupenthixol nor apomorphine at any dose substituted for morphine, but both apomorphine and flupenthixol disrupted expression of the morphine OS. This inhibition was specific to sucrose seeking during CS presentations rather than during the period before CS onset and, in the case of apomorphine more so than flupenthixol, to trials on which access to sucrose was anticipated. CONCLUSIONS Our findings lend support to a mechanism of occasion setting involving gating of CS-induced dopamine release rather than by direct dopaminergic modulation by the morphine stimulus.
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Affiliation(s)
- Davin R Peart
- Department of Psychology, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada
- Collaborative Neurosciences Graduate Program, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada
| | - Caitlin J Nolan
- Collaborative Neurosciences Graduate Program, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada
- Department of Biomedical Sciences, University of Guelph, Guelph, ON, Canada
| | - Adiia P Stone
- Department of Psychology, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada
- Collaborative Neurosciences Graduate Program, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada
| | - Mckenna A Williams
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Jessica M Karlovcec
- Department of Psychology, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada
- Collaborative Neurosciences Graduate Program, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada
| | - Jennifer E Murray
- Department of Psychology, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada.
- Collaborative Neurosciences Graduate Program, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada.
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Honeycutt S, Mukherjee A, Paladino M, Gilles-Thomas E, Loney G. Adolescent nicotine exposure promotes adulthood opioid consumption that persists despite adverse consequences and increases the density of insular perineuronal nets. ADDICTION NEUROSCIENCE 2024; 11:100150. [PMID: 38911872 PMCID: PMC11192509 DOI: 10.1016/j.addicn.2024.100150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/25/2024]
Abstract
Adolescence marks a sensitive period for neurodevelopment wherein exposure to drugs of abuse may disrupt maturation and induce persistent changes in neurophysiology which may exacerbate the risk for developing substance use disorders in adulthood. Adolescent nicotine exposure (ANE) enhances motivation to obtain drugs of abuse, particularly opioids, and increases vulnerability for the development of opioid use disorder (OUD). Here, we characterized ANE effects on learning about the adverse consequences of opioid consumption in adulthood in the absence of further nicotine administration. First, we show that ANE engenders punishment resistant fentanyl self-administration in a heterogenous seeking-taking chain schedule of reinforcement at least at the tested dose of fentanyl (0.75 μg/kg). We found that ANE rats consumed significantly more fentanyl and contingent foot shock punishment was less efficacious in limiting fentanyl seeking in ANE rats, relative to nicotine-naïve controls. Next, we demonstrated that ANE limits learning about the deleterious consequences of acute opioid intoxication in adulthood. In a combined conditioned taste avoidance and place preference paradigm we found that ANE resulted in significant reductions in the strength of morphine-induced CTA, and a simultaneous enhancement of CPP at a higher dose that was less capable of driving reinforcement in naïve controls. Finally, we examined the expression of perineuronal nets (PNNs) within insular cortex (IC) and found ANE rats to have increased density of PNNs across the anterior IC and significantly more parvalbumin-labeled IC cells relative to naïve controls. Together, these data lay the framework for a mechanistic explanation of the extreme comorbidity between nicotine use and development of OUDs.
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Peart DR, Claridge EV, Karlovcec JM, El Azali R, LaDouceur KE, Sikic A, Thomas A, Stone AP, Murray JE. Generalization of a positive-feature interoceptive morphine occasion setter across the rat estrous cycle. Horm Behav 2024; 162:105541. [PMID: 38583235 DOI: 10.1016/j.yhbeh.2024.105541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Revised: 03/17/2024] [Accepted: 03/29/2024] [Indexed: 04/09/2024]
Abstract
INTRODUCTION Interoceptive stimuli elicited by drug administration acquire conditioned modulatory properties of the induction of conditioned appetitive behaviours by exteroceptive cues. This effect may be modeled using a drug discrimination task in which the drug stimulus is trained as a positive-feature (FP) occasion setter (OS) that disambiguates the relation between an exteroceptive light conditioned stimulus (CS) and a sucrose unconditioned stimulus (US). We previously reported that females are less sensitive to generalization of a FP morphine OS than males, so we investigated the role of endogenous ovarian hormones in this difference. METHODS Male and female rats received intermixed injections of 3.2 mg/kg morphine or saline before each daily training session. Training consisted of 8 presentations of the CS, each followed by access to sucrose on morphine, but not saline sessions. Following acquisiton, rats were tested for generalization of the morphine stimulus to 0, 1.0, 3.2, and 5.4 mg/kg morphine. Female rats were monitored for estrous cyclicity using vaginal cytology throughout the study. RESULTS Both sexes acquired stable drug discrimination. A gradient of generalization was measured across morphine doses and this behaviour did not differ by sex, nor did it differ across the estrous cycle in females. CONCLUSIONS Morphine generalization is independent of fluctuations in levels of sex and endogenous gonadal hormones in females under these experimental conditions.
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Affiliation(s)
- Davin R Peart
- Department of Psychology, University of Guelph, Guelph, ON, Canada; Collaborative Neurosciences Graduate Program, University of Guelph, Guelph, ON, Canada
| | - Ella V Claridge
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Jessica M Karlovcec
- Department of Psychology, University of Guelph, Guelph, ON, Canada; Collaborative Neurosciences Graduate Program, University of Guelph, Guelph, ON, Canada
| | - Rita El Azali
- Department of Psychology, University of Guelph, Guelph, ON, Canada; Collaborative Neurosciences Graduate Program, University of Guelph, Guelph, ON, Canada
| | - Kathleen E LaDouceur
- Department of Psychology, University of Guelph, Guelph, ON, Canada; Collaborative Neurosciences Graduate Program, University of Guelph, Guelph, ON, Canada
| | - Anita Sikic
- Department of Psychology, University of Guelph, Guelph, ON, Canada; Collaborative Neurosciences Graduate Program, University of Guelph, Guelph, ON, Canada
| | - Abina Thomas
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Adiia P Stone
- Department of Psychology, University of Guelph, Guelph, ON, Canada; Collaborative Neurosciences Graduate Program, University of Guelph, Guelph, ON, Canada
| | - Jennifer E Murray
- Department of Psychology, University of Guelph, Guelph, ON, Canada; Collaborative Neurosciences Graduate Program, University of Guelph, Guelph, ON, Canada.
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Sharp BM, Leng S, Huang J, Jones C, Chen H. Inbred rat heredity and sex affect oral oxycodone self-administration and augmented intake in long sessions: correlations with anxiety and novelty-seeking. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.11.26.568753. [PMID: 38076806 PMCID: PMC10705287 DOI: 10.1101/2023.11.26.568753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
Oxycodone abuse begins with prescription oral oxycodone, yet vulnerability factors determining abuse are largely undefined. We evaluated genetic vulnerability in a rat model of oral oxycodone self-administration (SA): increasing oxycodone concentration/session (0.025-0.1mg/ml; 1,4,16-h) followed by extinction and reinstatement. Active licks and oxycodone intake were greater in females than males during 4-h and 16-h sessions (p< 0.001). Each sex increased intake during 16-h vs 4-h sessions (p<2e-16), but a subset of strains dramatically augmented intake at 16-h (p=0.0005). Heritability (h 2) of active licks/4-h at increasing oxycodone dose ranged from 0.30-0.53. Under a progressive ratio schedule, breakpoints were strain-dependent (p<2e-16). Cued reinstatement was greater in females (p<0.001). Naive rats were assessed by elevated plus maze (EPM), open field (OF) and novel object interaction (NOI). We correlated these behaviors with 28 parameters of oxycodone SA. Anxiety-defining EPM traits were most associated with SA in both sexes, whereas more OF and NOI traits were SA-associated in males. Sex and heredity are major determinants of motivation to take and seek oxycodone; intake augments dramatically during extended access in specific strains; and pleiotropic genes affect anxiety and multiple SA parameters.
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Affiliation(s)
- Burt M Sharp
- Department of Genetics, Genomics and Informatics, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | - Shuangying Leng
- Department of Genetics, Genomics and Informatics, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | - Jun Huang
- Department of Pharmacology, Addiction Science and Toxicology, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | - Caroline Jones
- Department of Genetics, Genomics and Informatics, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | - Hao Chen
- Department of Pharmacology, Addiction Science and Toxicology, University of Tennessee Health Science Center, Memphis, Tennessee 38163
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Quave CB, Vasquez AM, Aquino-Miranda G, Bora EP, Chidomere CL, Zhang XO, Engelke DS, Do-Monte FH. Neural signatures of opioid-induced risk-taking behavior in the prelimbic prefrontal cortex. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.05.578828. [PMID: 38370807 PMCID: PMC10871263 DOI: 10.1101/2024.02.05.578828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Opioid use disorder occurs alongside impaired risk-related decision-making, but the underlying neural correlates are unclear. We developed a novel approach-avoidance conflict model using a modified conditioned place preference paradigm to study neural signals of risky opioid seeking in the prefrontal cortex, a region implicated in executive decision making. Upon establishment of morphine conditioned place preference, rats underwent a subsequent conflict test in which fear-inducing cat odor was introduced in the previously drug-paired side of the apparatus. While the saline control group avoided the cat odor side, the morphine group maintained preference for the paired side despite the presence of cat odor. K-means clustering identified two subsets of morphine-treated rats that exhibited either persistent drug seeking (Risk-Takers) or increased avoidance (Risk-Avoiders) during conflict. Single-unit recordings from the prelimbic cortex (PL) revealed decreased neuronal firing rates upon acute morphine exposure in both Risk-Takers and Risk-Avoiders, but this firing rate suppression was absent after repeated administration. Risk-Avoiders also displayed distinct post-morphine excitation in PL which persisted across conditioning. During the preference test, subpopulations of PL neurons in all groups were either excited or inhibited when rats entered the paired side. Interestingly, while this inhibitory signal was lost during the subsequent conflict test in both saline and Risk-Avoider groups, these inhibitory responses persisted in Risk-Takers. Our results suggest that loss of PL inhibition after opioid conditioning is associated with the formation of contextual reward memory. Furthermore, persistent PL inhibitory signaling in the drug-associated context during conflict may underlie increased risk taking following opioid exposure.
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Affiliation(s)
- Cana B. Quave
- Dept. of Neurobiology & Anatomy, The University of Texas Health Science Center, Houston, TX 77030, USA
- McGovern Medical School at UTHealth Houston, The University of Texas MD Anderson Cancer Center UTHealth Houston Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Andres M. Vasquez
- Dept. of Neurobiology & Anatomy, The University of Texas Health Science Center, Houston, TX 77030, USA
- Dept. of Neuroscience, Rice University, Houston, TX 77005, USA
| | - Guillermo Aquino-Miranda
- Dept. of Neurobiology & Anatomy, The University of Texas Health Science Center, Houston, TX 77030, USA
| | - Esha P. Bora
- Dept. of Neurobiology & Anatomy, The University of Texas Health Science Center, Houston, TX 77030, USA
| | - Chinenye L. Chidomere
- Dept. of Neurobiology & Anatomy, The University of Texas Health Science Center, Houston, TX 77030, USA
- Dept. of Biomedical Engineering, University of Houston, Houston, TX 77204, USA
| | - Xu O. Zhang
- Dept. of Neurobiology & Anatomy, The University of Texas Health Science Center, Houston, TX 77030, USA
- McGovern Medical School at UTHealth Houston, The University of Texas MD Anderson Cancer Center UTHealth Houston Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Douglas S. Engelke
- Dept. of Neurobiology & Anatomy, The University of Texas Health Science Center, Houston, TX 77030, USA
| | - Fabricio H. Do-Monte
- Dept. of Neurobiology & Anatomy, The University of Texas Health Science Center, Houston, TX 77030, USA
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Little KM, Kosten TA. Focus on fentanyl in females: Sex and gender differences in the physiological and behavioral effects of fentanyl. Front Neuroendocrinol 2023; 71:101096. [PMID: 37597668 DOI: 10.1016/j.yfrne.2023.101096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 08/08/2023] [Accepted: 08/16/2023] [Indexed: 08/21/2023]
Abstract
The prevalence of opioid use disorder and overdose continues to harm the U.S. population and is further exacerbated by the use of the synthetic opioid, fentanyl, and its analogs. Gender differences in the effects of fentanyl are not well understood. The present article reviews evidence for gender and sex differences in the physiological and behavioral effects of fentanyl in humans and animals. Biological sex seems to be a foundational driver in addiction vulnerability and affects mechanisms related to opioid use including fentanyl. Fentanyl has distinct pharmacodynamics and enhanced efficacy relative to other opioids that highlights the need to investigate how females may be uniquely altered by its use. Behavioral and physiological responses to fentanyl are found to differ by sex and gender in many cases, including outputs like affective symptoms, analgesia, tolerance, and withdrawal emphasizing the need for further research about the role of biological sex on fentanyl use.
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Affiliation(s)
- Kaitlyn M Little
- Department of Psychology, University of Houston, Houston, TX, United States
| | - Therese A Kosten
- Department of Psychology, University of Houston, Houston, TX, United States.
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Babb JA, Constantino NJ, Kaplan GB, Chartoff EH. Estrous cycle dependent expression of oxycodone conditioned reward in rats. Sci Rep 2023; 13:13946. [PMID: 37626154 PMCID: PMC10457365 DOI: 10.1038/s41598-023-40971-3] [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] [Received: 05/03/2023] [Accepted: 08/19/2023] [Indexed: 08/27/2023] Open
Abstract
Oxycodone is one of the most widely prescribed and misused opioid painkillers in the United States. Evidence suggests that biological sex and hormonal status can impact drug reward in humans and rodents, but the extent to which these factors can influence the rewarding effects of oxycodone is unclear. The purpose of this study was to utilize place conditioning to determine the effects of sex and female hormonal status on the expression of oxycodone conditioned reward in rats. Gonadally intact adult Sprague-Dawley male and female rats were used to test: (1) whether both sexes express conditioned reward to oxycodone at similar doses, (2) the impact of conditioning session length on oxycodone conditioned reward expression in both sexes, and (3) the influence of female estrous cycle stage on oxycodone conditioned reward expression. Both sexes expressed conditioned reward at the same doses of oxycodone. Increasing the length of conditioning sessions did not reveal an effect of sex and resulted in lower magnitude conditioned reward expression. Importantly however, female stage of estrous cycle significantly influenced oxycodone conditioned reward expression. These results suggest that female hormonal status can impact the rewarding effects of opioids and thus have important implications for prescription opioid treatment practices.
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Affiliation(s)
- Jessica A Babb
- Research and Mental Health Services, VA Boston Healthcare System, Boston, Massachusetts, USA.
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, USA.
| | | | - Gary B Kaplan
- Research and Mental Health Services, VA Boston Healthcare System, Boston, Massachusetts, USA
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, USA
- Department of Psychiatry, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Elena H Chartoff
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, USA
- Division of Basic Neuroscience, McLean Hospital, Belmont, Massachusetts, USA
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Yates JR. Quantifying conditioned place preference: a review of current analyses and a proposal for a novel approach. Front Behav Neurosci 2023; 17:1256764. [PMID: 37693282 PMCID: PMC10484009 DOI: 10.3389/fnbeh.2023.1256764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 08/02/2023] [Indexed: 09/12/2023] Open
Abstract
Conditioned place preference (CPP) is used to measure the conditioned rewarding effects of a stimulus, including food, drugs, and social interaction. Because various analytic approaches can be used to quantify CPP, this can make direct comparisons across studies difficult. Common methods for analyzing CPP involve comparing the time spent in the CS+ compartment (e.g., compartment paired with drug) at posttest to the time spent in the CS+ compartment at pretest or to the CS- compartment (e.g., compartment paired with saline) at posttest. Researchers can analyze the time spent in the compartment(s), or they can calculate a difference score [(CS+post - CS+pre) or (CS+post - CS-post)] or a preference ratio (e.g., CS+post/(CS+post + CS-post)). While each analysis yields results that are, overall, highly correlated, there are situations in which different analyses can lead to discrepant interpretations. The current paper discusses some of the limitations associated with current analytic approaches and proposes a novel method for quantifying CPP, the adjusted CPP score, which can help resolve the limitations associated with current approaches. The adjusted CPP score is applied to both hypothetical and previously published data. Another major topic covered in this paper is methodologies for determining if individual subjects have met criteria for CPP. The paper concludes by highlighting ways in which researchers can increase transparency and replicability in CPP studies.
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Affiliation(s)
- Justin R. Yates
- Department of Psychological Science, Northern Kentucky University, Highland Heights, KY, United States
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9
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Kalamarides DJ, Singh A, Wolfman SL, Dani JA. Sex differences in VTA GABA transmission and plasticity during opioid withdrawal. Sci Rep 2023; 13:8460. [PMID: 37231124 DOI: 10.1038/s41598-023-35673-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 05/19/2023] [Indexed: 05/27/2023] Open
Abstract
The effectiveness of current treatments for opioid use disorder (OUD) varies by sex. Our understanding of the neurobiological mechanisms mediating negative states during withdrawal is lacking, particularly with regard to sex differences. Based on preclinical research in male subjects, opioid withdrawal is accompanied by increased gamma-aminobutyric acid (GABA) release probability at synapses onto dopamine neurons in the ventral tegmental area (VTA). It is unclear, however, if the physiological consequences of morphine that were originally elucidated in male rodents extend to females. The effects of morphine on the induction of future synaptic plasticity are also unknown. Here, we show that inhibitory synaptic long-term potentiation (LTPGABA) is occluded in the VTA in male mice after repeated morphine injections and 1 day of withdrawal, while morphine-treated female mice maintain the ability to evoke LTPGABA and have basal GABA activity similar to controls. Our observation of this physiological difference between male and female mice connects previous reports of sex differences in areas upstream and downstream of the GABA-dopamine synapse in the VTA during opioid withdrawal. The sex differences highlight the mechanistic distinctions between males and females that can be targeted when designing and implementing treatments for OUD.
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Affiliation(s)
- Daniel J Kalamarides
- Department of Neuroscience, Perelman School of Medicine, Mahoney Institute for Neurosciences, University of Pennsylvania, 415 Curie Blvd, Philadelphia, PA, 19104, USA
| | - Aditi Singh
- Department of Neuroscience, Perelman School of Medicine, Mahoney Institute for Neurosciences, University of Pennsylvania, 415 Curie Blvd, Philadelphia, PA, 19104, USA
| | - Shannon L Wolfman
- Department of Neuroscience, Perelman School of Medicine, Mahoney Institute for Neurosciences, University of Pennsylvania, 415 Curie Blvd, Philadelphia, PA, 19104, USA
| | - John A Dani
- Department of Neuroscience, Perelman School of Medicine, Mahoney Institute for Neurosciences, University of Pennsylvania, 415 Curie Blvd, Philadelphia, PA, 19104, USA.
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Armstrong C, Ferrante J, Lamichhane N, Reavis Z, Walker D, Patkar A, Kuhn C. Rapastinel accelerates loss of withdrawal signs after repeated morphine and blunts relapse to conditioned place preference. Pharmacol Biochem Behav 2022; 221:173485. [PMID: 36302442 DOI: 10.1016/j.pbb.2022.173485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 10/18/2022] [Accepted: 10/19/2022] [Indexed: 11/07/2022]
Abstract
The purpose of the present study was to evaluate the efficacy of rapastinel, an allosteric modulator of NMDA receptor function, to accelerate the loss of opioid withdrawal symptoms and blunt or prevent relapse to morphine conditioned place preference (CPP) in rats. Two studies were conducted. In study 1, adult and adolescent male and female rats were treated with increasing doses of morphine (5 mg/kg, bid to 25 mg/kg bid) for 5 days. On day 6 animals were treated with naloxone (1 mg/kg) and withdrawal was assessed. They were then treated with saline or rapastinel (5 mg/kg) on days 6 and 8, and withdrawal was assessed on day 9. Rapastinel treated animals exhibited significantly lower levels of withdrawal signs on day 9. No sex or age differences were observed. In Study 2, CPP for morphine was established in adult rats (males and females) by 4 daily pairings with saline and morphine (am/pm alternation). They were tested for CPP on day 5, and then treated with rapastinel (5 mg/kg) or saline daily on days 6-10 of extinction. On day 11 they received a final dose of rapastinel or saline followed by extinction trial. On day 12, animals received 1 mg/kg of morphine and were tested for relapse. Rapastinel did not affect extinction of CPP, but rapastinel-treated animals spent significantly less time in the previously morphine-paired side than saline-treated animals during the relapse trial. These findings of accelerated loss of withdrawal signs and blunted relapse to CPP suggest that rapastinel could provide an adjunctive therapy for opioid dependence during initiation of pharmacotherapy for opioid dependence.
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Affiliation(s)
- Christopher Armstrong
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, United States of America
| | - Julia Ferrante
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, United States of America; Department of Psychiatry, Duke University Medical Center, Durham, NC 27710, United States of America
| | - Nidesh Lamichhane
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, United States of America; Department of Psychiatry, Duke University Medical Center, Durham, NC 27710, United States of America
| | - Zachery Reavis
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, United States of America; Department of Psychiatry, Duke University Medical Center, Durham, NC 27710, United States of America
| | - David Walker
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, United States of America; Department of Psychiatry, Duke University Medical Center, Durham, NC 27710, United States of America
| | - Ashwin Patkar
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, United States of America; Department of Psychiatry, Duke University Medical Center, Durham, NC 27710, United States of America; Avance Psychiatry, 7850 Brier Creek Pkwy, Ste. 102, Raleigh, NC 27617, United States of America
| | - Cynthia Kuhn
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, United States of America; Department of Psychiatry, Duke University Medical Center, Durham, NC 27710, United States of America.
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Cippitelli A, Martinez M, Zribi G, Cami-Kobeci G, Husbands SM, Toll L. PPL-138 (BU10038): A bifunctional NOP/mu partial agonist that reduces cocaine self-administration in rats. Neuropharmacology 2022; 211:109045. [PMID: 35378170 PMCID: PMC9074796 DOI: 10.1016/j.neuropharm.2022.109045] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 03/11/2022] [Accepted: 03/21/2022] [Indexed: 12/30/2022]
Abstract
The search for new and effective treatments for cocaine use disorder (CUD) is a priority. We determined whether PPL-138 (BU10038), a compound with partial agonist activity at both nociceptin opioid peptide (NOP) and mu-opioid receptors, reduces cocaine consumption, reinstatement, and whether the compound itself produces reinforcing effects in rats. Using an intermittent access (IntA) cocaine self-administration procedure, we found that PPL-138 (0.1 and 0.3 mg/kg) effectively decreased the total number of cocaine infusions and burst-like cocaine intake in both male and female rats. Responses for food in an IntA model of food self-administration were not altered for either sex, although locomotor activity was increased in female but not male rats. Blockade of NOP receptors with the selective antagonist J-113397 (5 mg/kg) did not prevent the PPL-138-induced suppression of cocaine self-administration, whereas blockade of mu-opioid receptors by naltrexone (1 mg/kg) reversed such effect. Consistently, treatment with morphine (1, 3, and 10 mg/kg) dose-dependently reduced IntA cocaine self-administration measures. PPL-138 also reduced reinstatement of cocaine seeking at all doses examined. Although an initial treatment with PPL-138 (2.5, 10, and 40 μg/kg/infusion) appeared rewarding, the compound did not maintain self-administration behavior. Animals treated with PPL-138 showed initial suppression of cocaine self-administration, which was eliminated following repeated daily dosing. However, suppression of cocaine self-administration was retained when subsequent PPL-138 treatments were administered 48 h apart. These findings demonstrate that the approach of combining partial NOP/mu-opioid activation successfully reduces cocaine use, but properties of PPL-138 seem to depend on the timing of drug administration.
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Affiliation(s)
- Andrea Cippitelli
- Biomedical Science Department, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, United States.
| | - Madeline Martinez
- Biomedical Science Department, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, United States
| | - Gilles Zribi
- Biomedical Science Department, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, United States
| | - Gerta Cami-Kobeci
- School of Life Sciences, Faculty of Creative Arts, Technologies & Science, University of Bedfordshire Luton, Luton, UK
| | | | - Lawrence Toll
- Biomedical Science Department, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, United States
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12
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Shahzadi A, Yunusoglu O, Karabulut E, Sonmez H, Yazici Z. Influence of Selective Dopamine Agonist Ropinirole on Conditioned Place Preference and Somatic Signs of Morphine Withdrawal in Rats. Front Behav Neurosci 2022; 16:855241. [PMID: 35733518 PMCID: PMC9207507 DOI: 10.3389/fnbeh.2022.855241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 04/04/2022] [Indexed: 11/13/2022] Open
Abstract
The underlying mechanism of dependence and rewarding effects of morphine is imperative to understand. The primary aim of this study was to investigate whether ropinirole D2/3 agonist affects the rewarding and reinforcing properties of morphine-induced conditioned place preference (CPP) and withdrawal syndromes in rats. On day one, the animals were randomly divided to conduct the pre-test. The morphine (10 mg/kg, i.p.) and/or saline was administered on alternate days in an 8-day CPP session. On day 10, 15 min prior to the post-conditioning test (expression), a single dose of ropinirole (1, 2, and 5 mg/kg, i.p.) was given to rats. In extinction session, ropinirole was injected daily, and CPP was extinguished by repeated testing, with intervals of 3 days. Finally, reinstatement was assessed by administering ropinirole (1, 2, and 5 mg/kg) 15 min before the morphine injection. Morphine dependence was developed by administering increasing doses of morphine (10–50 mg/kg, i.p.). To assess withdrawal symptoms, ropinirole (1, 2, and 5 mg/kg) was injected 15 min before naloxone (2 mg/kg, s.c.) administration. The present study confirms that ropinirole attenuates expression and reinstatement of CPP, while it precipitates the extinction of morphine-induced CPP. Naloxone-precipitated morphine withdrawal symptoms, including wet dog shakes and weight loss, were attenuated although jumping was increased by a single ropinirole injection. Thus, ropinirole was influential in attenuating expression, reducing drug seeking and weakening reinstatement via the dopaminergic system. These findings show that ropinirole might affect neuro-adaptive changes related to dependence.
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Affiliation(s)
- Andleeb Shahzadi
- Department of Medical Pharmacology, Faculty of Medicine-Cerrahpasa, Istanbul University-Cerrahpasa, Istanbul, Turkey
- *Correspondence: Andleeb Shahzadi,
| | - Oruc Yunusoglu
- Department of Medical Pharmacology, Faculty of Medicine-Cerrahpasa, Istanbul University-Cerrahpasa, Istanbul, Turkey
- Department of Medical Pharmacology, Faculty of Medicine, Bolu Abant Izzet Baysal University, Bolu, Turkey
| | - Enes Karabulut
- Department of Medical Pharmacology, Faculty of Medicine-Cerrahpasa, Istanbul University-Cerrahpasa, Istanbul, Turkey
- Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
| | - Haktan Sonmez
- Department of Medical Pharmacology, Faculty of Medicine-Cerrahpasa, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Zeliha Yazici
- Department of Medical Pharmacology, Faculty of Medicine-Cerrahpasa, Istanbul University-Cerrahpasa, Istanbul, Turkey
- Department of Medical Pharmacology, Faculty of Medicine, Biruni University, Istanbul, Turkey
- Zeliha Yazici, ;
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13
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Romanescu M, Buda V, Lombrea A, Andor M, Ledeti I, Suciu M, Danciu C, Dehelean CA, Dehelean L. Sex-Related Differences in Pharmacological Response to CNS Drugs: A Narrative Review. J Pers Med 2022; 12:jpm12060907. [PMID: 35743692 PMCID: PMC9224918 DOI: 10.3390/jpm12060907] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/23/2022] [Accepted: 05/26/2022] [Indexed: 02/07/2023] Open
Abstract
In the last decades, both animal and human studies have neglected female subjects with the aim of evading a theorized intricacy of feminine hormonal status. However, clinical experience proves that pharmacological response may vary between the two sexes since pathophysiological dissimilarities between men and women significantly influence the pharmacokinetics and pharmacodynamics of drugs. Sex-related differences in central nervous system (CNS) medication are particularly challenging to assess due to the complexity of disease manifestation, drugs’ intricate mechanisms of action, and lack of trustworthy means of evaluating the clinical response to medication. Although many studies showed contrary results, it appears to be a general tendency towards a certain sex-related difference in each pharmacological class. Broadly, opioids seem to produce better analgesia in women especially when they are administered for a prolonged period of time. On the other hand, respiratory and gastrointestinal adverse drug reactions (ADRs) following morphine therapy are more prevalent among female patients. Regarding antidepressants, studies suggest that males might respond better to tricyclic antidepressants (TCAs), whereas females prefer selective serotonin reuptake inhibitors (SSRI), probably due to their tolerance to particular ADRs. In general, studies missed spotting any significant sex-related differences in the therapeutic effect of antiepileptic drugs (AED), but ADRs have sex variations in conjunction with sex hormones’ metabolism. On the subject of antipsychotic therapy, women appear to have a superior response to this pharmacological class, although there are also studies claiming the opposite. However, it seems that reported sex-related differences regarding ADRs are steadier: women are more at risk of developing various side effects, such as metabolic dysfunctions, cardiovascular disorders, and hyperprolactinemia. Taking all of the above into account, it seems that response to CNS drugs might be occasionally influenced by sex as a biological variable. Nonetheless, although for each pharmacological class, studies generally converge to a certain pattern, opposite outcomes are standing in the way of a clear consensus. Hence, the fact that so many studies are yielding conflicting results emphasizes once again the need to address sex-related differences in pharmacological response to drugs.
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Affiliation(s)
- Mirabela Romanescu
- Faculty of Pharmacy, “Victor Babeş” University of Medicine and Pharmacy, 2 Eftimie Murgu Street, 300041 Timisoara, Romania; (M.R.); (A.L.); (I.L.); (M.S.); (C.D.); (C.A.D.)
| | - Valentina Buda
- Faculty of Pharmacy, “Victor Babeş” University of Medicine and Pharmacy, 2 Eftimie Murgu Street, 300041 Timisoara, Romania; (M.R.); (A.L.); (I.L.); (M.S.); (C.D.); (C.A.D.)
- Research Center for Pharmaco-Toxicological Evaluation, “Victor Babes” University of Medicine and Pharmacy, 2 Eftimie Murgu Square, 300041 Timisoara, Romania
- Correspondence: ; Tel.: +40-755-100-408
| | - Adelina Lombrea
- Faculty of Pharmacy, “Victor Babeş” University of Medicine and Pharmacy, 2 Eftimie Murgu Street, 300041 Timisoara, Romania; (M.R.); (A.L.); (I.L.); (M.S.); (C.D.); (C.A.D.)
- Research Center for Pharmaco-Toxicological Evaluation, “Victor Babes” University of Medicine and Pharmacy, 2 Eftimie Murgu Square, 300041 Timisoara, Romania
| | - Minodora Andor
- Faculty of Medicine, “Victor Babeş” University of Medicine and Pharmacy, 2 Eftimie Murgu Street, 300041 Timisoara, Romania; (M.A.); (L.D.)
| | - Ionut Ledeti
- Faculty of Pharmacy, “Victor Babeş” University of Medicine and Pharmacy, 2 Eftimie Murgu Street, 300041 Timisoara, Romania; (M.R.); (A.L.); (I.L.); (M.S.); (C.D.); (C.A.D.)
- Advanced Instrumental Screening Center, “Victor Babes” University of Medicine and Pharmacy, 2 Eftimie Murgu Square, 300041 Timisoara, Romania
| | - Maria Suciu
- Faculty of Pharmacy, “Victor Babeş” University of Medicine and Pharmacy, 2 Eftimie Murgu Street, 300041 Timisoara, Romania; (M.R.); (A.L.); (I.L.); (M.S.); (C.D.); (C.A.D.)
| | - Corina Danciu
- Faculty of Pharmacy, “Victor Babeş” University of Medicine and Pharmacy, 2 Eftimie Murgu Street, 300041 Timisoara, Romania; (M.R.); (A.L.); (I.L.); (M.S.); (C.D.); (C.A.D.)
- Research Center for Pharmaco-Toxicological Evaluation, “Victor Babes” University of Medicine and Pharmacy, 2 Eftimie Murgu Square, 300041 Timisoara, Romania
| | - Cristina Adriana Dehelean
- Faculty of Pharmacy, “Victor Babeş” University of Medicine and Pharmacy, 2 Eftimie Murgu Street, 300041 Timisoara, Romania; (M.R.); (A.L.); (I.L.); (M.S.); (C.D.); (C.A.D.)
- Research Center for Pharmaco-Toxicological Evaluation, “Victor Babes” University of Medicine and Pharmacy, 2 Eftimie Murgu Square, 300041 Timisoara, Romania
| | - Liana Dehelean
- Faculty of Medicine, “Victor Babeş” University of Medicine and Pharmacy, 2 Eftimie Murgu Street, 300041 Timisoara, Romania; (M.A.); (L.D.)
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14
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Sharp JL, Pearson T, Smith MA. Sex differences in opioid receptor mediated effects: Role of androgens. Neurosci Biobehav Rev 2022; 134:104522. [PMID: 34995646 PMCID: PMC8872632 DOI: 10.1016/j.neubiorev.2022.104522] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/19/2021] [Accepted: 01/02/2022] [Indexed: 12/26/2022]
Abstract
An abundance of data indicates there are sex differences in endogenous opioid peptides and opioid receptors, leading to functional differences in sensitivity to opioid receptor mediated behaviors between males and females. Many of these sex differences are mediated by the effects of gonadal hormones on the endogenous opioid system. Whereas much research has examined the role of ovarian hormones on opioid receptor mediated endpoints, comparatively less research has examined the role of androgens. This review describes what is currently known regarding the influence of androgens on opioid receptor mediated endpoints and how androgens may contribute to sex differences in these effects. The review also addresses the clinical implications of androgenic modulation of opioid receptor mediated behaviors and suggests future lines of research for preclinical and clinical investigators. We conclude that further investigation into androgenic modulation of opioid receptor mediated effects may lead to new options for addressing conditions such as chronic pain and substance use disorders.
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Affiliation(s)
- Jessica L Sharp
- Department of Psychology and Program in Neuroscience, Davidson College, United States
| | - Tallia Pearson
- Department of Psychology and Program in Neuroscience, Davidson College, United States
| | - Mark A Smith
- Department of Psychology and Program in Neuroscience, Davidson College, United States.
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15
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Askari N, Mousavi A, Vaez-Mahdavi MR. Maternal deprivation effect on morphine-induced CPP is related to changes in Opioid receptors in selected rat brain regions (hippocampus, prefrontal cortex, and nucleus accumbens). Behav Processes 2022; 197:104607. [PMID: 35218881 DOI: 10.1016/j.beproc.2022.104607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 02/19/2022] [Accepted: 02/20/2022] [Indexed: 11/16/2022]
Abstract
Early-life environmental conditions affect offspring's development. Maternal deprivation (MD) can induce persistent changes that give rise to neuropsychiatric diseases including substance abuse disorders. However, long-lasting mechanisms that determine vulnerability to drug addiction remain unknown. We hypothesized that MD could induce changes in Opioid system, HPA (hypothalamic-pituitary-adrenal) axis, and BDNF (brain-derived neurotrophic factor), so may be involved in the drug abuse in later life. Male offspring of Wistar rats (n=8 per group) were subjected to 3h of daily MD during postnatal days 1-14. In adulthood, morphine-induced CPP (conditioned place preference) was investigated using two doses of morphine (3 and 5mg/kg). Serum corticosterone level was measured by ELISA method. The expression level of genes in selected brain regions (hippocampus, prefrontal cortex, and nucleus accumbens) was determined by qPCR (quantitative PCR). A greater morphine-induced CPP was observed in MD rats with 3 and 5mg/kg morphine compared to controls. MD group had a higher corticosterone level. A significant decrease was observed in the expression of BDNF gene (in all of the selected brain regions) and GR (glucocorticoid receptor) gene (in the hippocampus and nucleus accumbens) in MD rats. Also, a significant increase in the expression of μ Opioid receptor (in all of the selected brain regions) and κ Opioid receptor (in the prefrontal cortex and nucleus accumbens) was observed in MD rats. Our results suggest that MD induces alterations in the HPA axis function, BDNF level, and Opioid receptors system that enhance vulnerability to morphine at adulthood.
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Affiliation(s)
- Nayere Askari
- Department of Biology, Faculty of Sciences, Shahid Bahonar University of Kerman, Kerman, I.R. Iran; Immunoregulation Research Center, Shahed University, Tehran, I.R. Iran.
| | - Ali Mousavi
- Department of Biology, Faculty of Sciences, Shahid Bahonar University of Kerman, Kerman, I.R. Iran
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16
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Gaulden AD, Burson N, Sadik N, Ghosh I, Khan S, Brummelte S, Kallakuri S, Perrine SA. Effects of fentanyl on acute locomotor activity, behavioral sensitization, and contextual reward in female and male rats. Drug Alcohol Depend 2021; 229:109101. [PMID: 34628096 PMCID: PMC8671359 DOI: 10.1016/j.drugalcdep.2021.109101] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 09/05/2021] [Accepted: 09/20/2021] [Indexed: 12/01/2022]
Abstract
BACKGROUND Although fentanyl has gained widespread prominence, there remains a lack of knowledge on this opioid synthetic agonist, particularly related to sex effects. Therefore, we conducted behavioral tests in female and male rats to measure drug abuse-related responses to fentanyl hypothesizing sex-specific responses. METHODS Using female and male rats, we measured the effects of acute or repeated administration of fentanyl (20 μg/kg) on locomotor activity (LMA) and behavioral sensitization in an open field test. We further measured contextual-reward and associated locomotor activity during training in a conditioned place preference (CPP) paradigm using a low (4 μg/kg) or high (16 μg/kg) dose of fentanyl. Vaginal lavage samples were collected from female rats in the CPP study, and the estrous phase was determined based on the cytological characterization. RESULTS Female, but not male, rats showed elevated LMA in response to acute fentanyl and behavioral sensitization to repeated administration of fentanyl. Fentanyl produced significant CPP in both sexes, but it was more potent in males. Finally, our secondary investigation of the estrous cycle on fentanyl-CPP suggests that non-estrus phases, likely reflecting high estradiol, may predict the degree of fentanyl preference in females. CONCLUSIONS Fentanyl was more potent and/or effective to produce LMA and LMA sensitization in females but more potent to produce CPP in males. Furthermore, the role of sex in fentanyl responses varied across endpoints, and sex differences in LMA were not predictive of sex differences in CPP.
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Affiliation(s)
- Andrew D. Gaulden
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI.,Translational Neuroscience Program, Wayne State University School of Medicine, Detroit, MI
| | - Nicole Burson
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI
| | - Nareen Sadik
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI.,Research Services, John D. Dingell VA Medical Center, Detroit, MI
| | - Ishita Ghosh
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI
| | - Sabrina Khan
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI
| | - Susanne Brummelte
- Translational Neuroscience Program, Wayne State University School of Medicine, Detroit, MI.,Department of Psychology, Wayne State University, Detroit, MI
| | - Srinivasu Kallakuri
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI.,Research Services, John D. Dingell VA Medical Center, Detroit, MI
| | - Shane A. Perrine
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI.,Translational Neuroscience Program, Wayne State University School of Medicine, Detroit, MI.,Research Services, John D. Dingell VA Medical Center, Detroit, MI
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17
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Gupta A, Gullapalli S, Pan H, Ramos-Ortolaza DL, Hayward MD, Low MJ, Pintar JE, Devi LA, Gomes I. Regulation of Opioid Receptors by Their Endogenous Opioid Peptides. Cell Mol Neurobiol 2021; 41:1103-1118. [PMID: 33389463 DOI: 10.1007/s10571-020-01015-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 11/18/2020] [Indexed: 11/25/2022]
Abstract
Activation of μ, δ, and κ opioid receptors by endogenous opioid peptides leads to the regulation of many emotional and physiological responses. The three major endogenous opioid peptides, β-endorphin, enkephalins, and dynorphins result from the processing of three main precursors: proopiomelanocortin, proenkephalin, and prodynorphin. Using a knockout approach, we sought to determine whether the absence of endogenous opioid peptides would affect the expression or activity of opioid receptors in mice lacking either proenkephalin, β-endorphin, or both. Since gene knockout can lead to changes in the levels of peptides generated from related precursors by compensatory mechanisms, we directly measured the levels of Leu-enkephalin and dynorphin-derived peptides in the brain of animals lacking proenkephalin, β-endorphin, or both. We find that whereas the levels of dynorphin-derived peptides were relatively unaltered, the levels of Leu-enkephalin were substantially decreased compared to wild-type mice suggesting that preproenkephalin is the major source of Leu-enkephalin. This data also suggests that the lack of β-endorphin and/or proenkephalin does not lead to a compensatory change in prodynorphin processing. Next, we examined the effect of loss of the endogenous peptides on the regulation of opioid receptor levels and activity in specific regions of the brain. We also compared the receptor levels and activity in males and females and show that the lack of β-endorphin and/or proenkephalin leads to differential modulation of the three opioid receptors in a region- and gender-specific manner. These results suggest that endogenous opioid peptides are important modulators of the expression and activity of opioid receptors in the brain.
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Affiliation(s)
- Achla Gupta
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1603, New York, NY, 10029, USA
| | - Srinivas Gullapalli
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1603, New York, NY, 10029, USA
- Emcure Pharmaceuticals, Mumbai, India
| | - Hui Pan
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1603, New York, NY, 10029, USA
- University of Southern California Medical Center, Los Angeles, CA, USA
| | - Dinah L Ramos-Ortolaza
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1603, New York, NY, 10029, USA
- Pontifico Catholic Univ. Puerto Rico, Ponce, Puerto Rico
| | - Michael D Hayward
- Vollum Institute, Oregon Health Sciences University, Portland, OR, 97201, USA
- Invivotek, Trenton, NJ, USA
| | - Malcom J Low
- Vollum Institute, Oregon Health Sciences University, Portland, OR, 97201, USA
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - John E Pintar
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, 08854, USA
| | - Lakshmi A Devi
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1603, New York, NY, 10029, USA.
| | - Ivone Gomes
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1603, New York, NY, 10029, USA.
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18
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Fattore L, Marti M, Mostallino R, Castelli MP. Sex and Gender Differences in the Effects of Novel Psychoactive Substances. Brain Sci 2020; 10:brainsci10090606. [PMID: 32899299 PMCID: PMC7564810 DOI: 10.3390/brainsci10090606] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 08/28/2020] [Accepted: 08/31/2020] [Indexed: 12/12/2022] Open
Abstract
Sex and gender deeply affect the subjective effects and pharmaco-toxicological responses to drugs. Men are more likely than women to use almost all types of illicit drugs and to present to emergency departments for serious or fatal intoxications. However, women are just as likely as men to develop substance use disorders, and may be more susceptible to craving and relapse. Clinical and preclinical studies have shown important differences between males and females after administration of “classic” drugs of abuse (e.g., Δ9-tetrahydrocannabinol (THC), morphine, cocaine). This scenario has become enormously complicated in the last decade with the overbearing appearance of the new psychoactive substances (NPS) that have emerged as alternatives to regulated drugs. To date, more than 900 NPS have been identified, and can be catalogued in different pharmacological categories including synthetic cannabinoids, synthetic stimulants (cathinones and amphetamine-like), hallucinogenic phenethylamines, synthetic opioids (fentanyls and non-fentanyls), new benzodiazepines and dissociative anesthetics (i.e., methoxetamine and phencyclidine-derivatives). This work collects the little knowledge reached so far on the effects of NPS in male and female animal and human subjects, highlighting how much sex and gender differences in the effects of NPS has yet to be studied and understood.
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Affiliation(s)
- Liana Fattore
- Institute of Neuroscience-Cagliari, National Research Council (CNR), Cittadella Universitaria, 09042 Monserrato, Cagliari, Italy
- Correspondence:
| | - Matteo Marti
- Department of Morphology, Surgery and Experimental Medicine, Section of Legal Medicine and LTTA Center, University of Ferrara, 44121 Ferrara, Italy;
- Department of Anti-Drug Policies, Collaborative Center for the Italian National Early Warning System, Presidency of the Council of Ministers, 00187 Rome, Italy
| | - Rafaela Mostallino
- Department of Biomedical Sciences, Division of Neuroscience and Clinical Pharmacology, University of Cagliari, Cittadella Universitaria, 09042 Monserrato, Cagliari, Italy; (R.M.); (M.P.C.)
| | - Maria Paola Castelli
- Department of Biomedical Sciences, Division of Neuroscience and Clinical Pharmacology, University of Cagliari, Cittadella Universitaria, 09042 Monserrato, Cagliari, Italy; (R.M.); (M.P.C.)
- National Institute of Neuroscience (INN), University of Cagliari, 09124 Cagliari, Italy
- Center of Excellence “Neurobiology of Addiction”, University of Cagliari, 09124 Cagliari, Italy
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19
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Lopresti NM, Esguerra M, Mermelstein PG. Sex Differences in Animal Models of Opioid Reward. CURRENT SEXUAL HEALTH REPORTS 2020; 12:186-194. [PMID: 33574737 PMCID: PMC7872138 DOI: 10.1007/s11930-020-00266-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE OF REVIEW This review aims to discuss sex differences observed in preclinical rodent models of opioid reward. RECENT FINDINGS Utilizing a variety of methodological approaches and drug regimens, no clear consensus has emerged regarding the effects of opiates between males and females. This is quite dissimilar to work examining psychostimulants, where female animals reliably exhibit stronger behavioral responses. SUMMARY With opioid research quickly expanding to determine the neural underpinnings of opioid addiction, further research is essential to determine the conditions wherein sex differences may occur and how they may relate to the human condition.
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Affiliation(s)
| | - Manuel Esguerra
- University of Minnesota, Twin Cities, Department of Neuroscience
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20
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Windisch KA, Kreek MJ. Review of addiction risk potential associated with adolescent opioid use. Pharmacol Biochem Behav 2020; 198:173022. [PMID: 32871141 DOI: 10.1016/j.pbb.2020.173022] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 08/18/2020] [Accepted: 08/26/2020] [Indexed: 01/31/2023]
Abstract
Adolescence is a critical period of development with robust behavioral, morphological, hormonal, and neurochemical changes including changes in brain regions implicated in the reinforcing effects of drugs such as opioids. Here we examine the preclinical and, where appropriate complementary clinical literature, for the behavioral and neurological changes induced by adolescent opioid exposure/use and their long-term consequences during adulthood. Adolescent opioid exposure results in a widened biphasic shift in reinforcement with increased impact of positive rewarding aspects during initial use and profound negative reinforcement during adulthood. Females may have enhanced vulnerability due to fast onset of antinociceptive tolerance and reduced severity of somatic withdrawal symptoms during adolescence. Overall, adolescent opioid exposure, be it legally prescribed protracted intake or illicit consumption, results in significant and prolonged consequences of increased opioid reward concomitant with reduced analgesic efficacy and exacerbated somatic withdrawal severity during opioid use/exposure in adulthood. These findings are highly relevant to physicians, parents, law makers, and the general public as adolescent opioid exposure/misuse results in heightened risk for substance use disorders.
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Affiliation(s)
- Kyle A Windisch
- Laboratory of the Biology of Addictive Diseases, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
| | - Mary Jeanne Kreek
- Laboratory of the Biology of Addictive Diseases, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
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21
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Green TA, Bardo MT. Opposite regulation of conditioned place preference and intravenous drug self-administration in rodent models: Motivational and non-motivational examples. Neurosci Biobehav Rev 2020; 116:89-98. [PMID: 32534899 DOI: 10.1016/j.neubiorev.2020.06.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 06/01/2020] [Accepted: 06/03/2020] [Indexed: 12/13/2022]
Abstract
Although developed from a common antecedent, conditioned place preference (CPP) and intravenous drug self-administration (SA) represent different behavioral paradigms, each with strong face validity. The field has treated results from these studies largely interchangeably; however, there is considerable evidence of opposite modulation of CPP vs. SA. This review outlines four manipulations that differentially affect CPP and SA based on alterations of motivation. These examples are contrasted with one example of differential CPP and SA results that can be explained by simple parallel shifts in dose-response functions. The final two examples have yet to be classified as motivation-based or parallel shifts. Important aspects, including motivation, volitional control of drug administration, reward, and the role of cues are discussed. One major conclusion of this paper is that explanations for apparent discrepancies between CPP and SA require full dose effect functions and assessment of PR breakpoints. Overall, this manuscript offers a more nuanced insight into how CPP and SA can be used to study different aspects of substance use disorders.
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Affiliation(s)
- Thomas A Green
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, United States.
| | - Michael T Bardo
- Department of Psychology, University of Kentucky, United States.
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22
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Ross JA, Van Bockstaele EJ. The role of catecholamines in modulating responses to stress: Sex-specific patterns, implications, and therapeutic potential for post-traumatic stress disorder and opiate withdrawal. Eur J Neurosci 2020; 52:2429-2465. [PMID: 32125035 DOI: 10.1111/ejn.14714] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 01/15/2020] [Accepted: 02/20/2020] [Indexed: 12/22/2022]
Abstract
Emotional arousal is one of several factors that determine the strength of a memory and how efficiently it may be retrieved. The systems at play are multifaceted; on one hand, the dopaminergic mesocorticolimbic system evaluates the rewarding or reinforcing potential of a stimulus, while on the other, the noradrenergic stress response system evaluates the risk of threat, commanding attention, and engaging emotional and physical behavioral responses. Sex-specific patterns in the anatomy and function of the arousal system suggest that sexually divergent therapeutic approaches may be advantageous for neurological disorders involving arousal, learning, and memory. From the lens of the triple network model of psychopathology, we argue that post-traumatic stress disorder and opiate substance use disorder arise from maladaptive learning responses that are perpetuated by hyperarousal of the salience network. We present evidence that catecholamine-modulated learning and stress-responsive circuitry exerts substantial influence over the salience network and its dysfunction in stress-related psychiatric disorders, and between the sexes. We discuss the therapeutic potential of targeting the endogenous cannabinoid system; a ubiquitous neuromodulator that influences learning, memory, and responsivity to stress by influencing catecholamine, excitatory, and inhibitory synaptic transmission. Relevant preclinical data in male and female rodents are integrated with clinical data in men and women in an effort to understand how ideal treatment modalities between the sexes may be different.
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Affiliation(s)
- Jennifer A Ross
- Department of Pharmacology and Physiology, College of Medicine, Drexel University, Philadelphia, PA, USA
| | - Elisabeth J Van Bockstaele
- Department of Pharmacology and Physiology, College of Medicine, Drexel University, Philadelphia, PA, USA
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Lee JR, Tapia MA, Weise VN, Bathe EL, Vieira-Potter VJ, Booth FW, Will MJ. Voluntary wheel running effects on intra-accumbens opioid driven diet preferences in male and female rats. Neuropharmacology 2019; 155:22-30. [PMID: 31100290 DOI: 10.1016/j.neuropharm.2019.05.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 05/08/2019] [Accepted: 05/13/2019] [Indexed: 10/26/2022]
Abstract
Palatability driven feeding and voluntary physical activity are mediated by and influence similar neural mechanisms, notably through the actions of opioids within the nucleus accumbens. Recent studies suggest that access to a voluntary running wheel results in sex dependent behavioral and physiological adaptations related to opioid mediated palatability-driven feeding. To explore this relationship, male and female Wistar rats were given either access to a voluntary running wheel (RUN group) or no access (SED group) for one week prior to being stereotaxically implanted with bilateral cannulae targeting the nucleus accumbens. Following 7 days of recovery, with RUN or SED conditions continuing the duration of the experiment, all rats were assessed daily (2 h/day) for feeding behavior of concurrently accessible high-carbohydrate and high-fat diet for one week. Following this week, all rats were administered the μ-opioid receptor agonist D-Ala2, NMe-Phe4, Glyol5-enkephalin (DAMGO) (0.0025 μg, 0.025 μg, or 0.25 μg/0.5 μl/side) or the opioid antagonist naloxone (20 μg/0.5 μl/side) into the nucleus accumbens and given concurrent access (2 h) to both diets. All groups expressed a significant baseline preference for the high-carbohydrate diet. DAMGO administration, compared to saline treatment, led to significant increased consumption of the high-carbohydrate diet in all treatment groups. While high-fat diet consumption also increased following DAMGO administration, the influence of DAMGO was much more robust for the preferred high-carbohydrate diet in all groups. Compared to males, females consumed significantly more of both diets at baseline and following DAMGO treatment. Both male and female rats in the RUN condition consumed more high-carbohydrate diet compared to rats in the SED condition. While males exhibited similar increased consumption of both diets regardless of RUN or SED condition, females in the RUN condition displayed a greater sensitivity to DAMGO-driven consumption of the preferred high-carbohydrate, compared to SED females.
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Affiliation(s)
- Jenna R Lee
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, USA
| | - Melissa A Tapia
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA
| | - Valerie N Weise
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA
| | - Emily L Bathe
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA
| | | | - Frank W Booth
- Department of Biomedical Sciences, University of Missouri, Columbia, MO, USA
| | - Matthew J Will
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, USA; Department of Psychological Sciences, University of Missouri, Columbia, MO, USA.
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Bobzean SAM, Kokane SS, Butler BD, Perrotti LI. Sex differences in the expression of morphine withdrawal symptoms and associated activity in the tail of the ventral tegmental area. Neurosci Lett 2019; 705:124-130. [PMID: 31042569 PMCID: PMC6662583 DOI: 10.1016/j.neulet.2019.04.057] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 04/17/2019] [Accepted: 04/26/2019] [Indexed: 01/18/2023]
Abstract
Recent studies, in male rodents, have begun to elucidate a role for the GABAergic neurons in the tail of the ventral tegmental area (tVTA) in morphine withdrawal. To date, the mechanisms underlying morphine withdrawal have been studied almost exclusively in male animals. As a result, there is a considerable gap in our current understanding of the processes underlying sex differences in morphine withdrawal behaviors and its effects on cellular activity in the tVTA in females. The purpose of the present study was to investigate the influence of sex on the expression and duration of spontaneous somatic morphine withdrawal syndrome, and to characterize the relationship between spontaneous somatic withdrawal symptoms and cellular activation (measured as phosphorylated CREB; pCREB), in the GABAergic tVTA in male and female rats. Morphine-dependent adult male and female Long Evans rats underwent 72 h of spontaneous withdrawal, and somatic withdrawal symptoms were assessed every 12 h. Male morphine-dependent rats expressed more severe symptoms during the early phases of withdrawal compared to females. Although, females demonstrated lower overall symptom severity, their symptoms persisted for a longer period of time, thus demonstrating higher withdrawal-symptom severity than males during late withdrawal. pCREB activity in the tVTA was elevated in morphine-withdrawn rats and was positively correlated with the severity of withdrawal symptoms. These results demonstrate sex differences in the timing of the expression of somatic withdrawal. Our data add to the growing body of evidence demonstrating a role for the tVTA in morphine withdrawal and begin to establish a sex-dependent behavioral and molecular profile within this brain region.
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Affiliation(s)
- Samara A M Bobzean
- Department of Psychology, College of Science, The University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Saurabh S Kokane
- Department of Psychology, College of Science, The University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Brandon D Butler
- Department of Psychology, College of Science, The University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Linda I Perrotti
- Department of Psychology, College of Science, The University of Texas at Arlington, Arlington, TX, 76019, USA.
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25
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Lee JR, Parker KE, Tapia M, Johns HW, Floros TG, Roberts MD, Booth FW, Will MJ. Voluntary wheel running effects on intra-accumbens opioid high-fat feeding and locomotor behavior in Sprague-Dawley and Wistar rat strains. Physiol Behav 2019; 206:67-75. [PMID: 30807769 DOI: 10.1016/j.physbeh.2019.02.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 01/29/2019] [Accepted: 02/11/2019] [Indexed: 12/30/2022]
Abstract
The present study examined the influence of physical activity vs. sedentary home cage conditions on baseline and opioid-driven high-fat feeding behaviors in two common strains of laboratory rats. Sprague-Dawley and Wistar rats were singly housed with either access to a voluntary running wheel (RUN) or locked-wheel (SED) for 5 weeks, before being stereotaxically implanted with bilateral cannulae targeting the nucleus accumbens. Following recovery, with RUN or SED conditions continuing the duration of the experiment, all rats were given 2 h daily access to a high-fat diet for 6 consecutive days to establish a stable baseline intake. Over the next 2 weeks, all subjects were administered the μ-opioid agonist D-Ala2, NMe-Phe4, Glyol5-enkephalin (DAMGO) (multiple dose range) or saline into the nucleus accumbens, immediately followed by 2 h access to a high-fat diet. Drug treatments were separated by at least 1 day and treatment order was counterbalanced. Baseline consumption of the high-fat diet during the 1-week baseline acclimation period did not differ between RUN and SED groups in either rat strain. Higher doses of DAMGO produced increased fat consumption in both strains of rats, yet no differences were observed between RUN vs. SED treated groups. However, SED treatment produced a greater locomotor response following intra-accumbens DAMGO administration, compared to the RUN condition, during the 2 h feeding session. The data suggest that the animals housed in sedentary versus voluntary wheel running conditions may differ in behavioral tolerance to the locomotor but not the orexigenic activating properties of intra-accumbens DAMGO treatment.
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Affiliation(s)
- Jenna R Lee
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, USA.
| | - Kyle E Parker
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA; Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, USA
| | - Melissa Tapia
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA
| | - Howard W Johns
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA
| | - Ted G Floros
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA
| | - Michael D Roberts
- Department of Biomedical Sciences, University of Missouri, Columbia, MO, USA
| | - Frank W Booth
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, USA; Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA; Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA
| | - Matthew J Will
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA; Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, USA.
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26
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Early life stress and the propensity to develop addictive behaviors. Int J Dev Neurosci 2019; 78:156-169. [PMID: 31255718 DOI: 10.1016/j.ijdevneu.2019.06.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 06/03/2019] [Accepted: 06/13/2019] [Indexed: 12/14/2022] Open
Abstract
There is a vast literature on effects of early life manipulations in rodents much of which is aimed at investigating the long-term consequences related to emotion and cognition in adulthood. Less is known about how these manipulations affect responses reflective of alcohol (AUD) and substance (SUD) use disorders. The purpose of this paper is to review the literature of studies that employed early life manipulations and assessed behavioral responses to psychoactive substances, specifically alcohol, opiates, and stimulants, in rodents. While the findings with alcohol are more limited and mixed, studies with opiates and stimulants show strong support for the ability of these manipulations to enhance behavioral responsivity to these substances in line with epidemiological data. Some outcomes show sex differences. The mechanisms that influence these enduring changes may reflect epigenetic alterations. Several studies support a role for altered DNA methylation (and other epigenetic mechanisms) as biological responses to early environmental insults. The chemical changes induced by DNA methylation affect transcriptional activity of DNA and thus can have a long-term impact on the individual's phenotype. Such effects are particularly robust when they occur during sensitive periods of brain development (e.g., first postnatal weeks in rodents). We review this emerging literature as it relates to the known neurobiology of AUDs and SUDs and suggest new avenues of research. Such findings will have implications for the treatment and prevention of AUDs and SUDs and could provide insight into factors that support resiliency.
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Fakira AK, Peck EG, Liu Y, Lueptow LM, Trimbake NA, Han MH, Calipari ES, Devi LA. The role of the neuropeptide PEN receptor, GPR83, in the reward pathway: Relationship to sex-differences. Neuropharmacology 2019; 157:107666. [PMID: 31199956 DOI: 10.1016/j.neuropharm.2019.107666] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 05/22/2019] [Accepted: 06/06/2019] [Indexed: 12/16/2022]
Abstract
GPR83, the receptor for the neuropeptide PEN, exhibits high expression in the nucleus accumbens of the human and rodent brain, suggesting that it plays a role in modulating the mesolimbic reward pathway. However, the cell-type specific expression of GPR83, its functional impact in the reward pathway, and in drug reward-learning has not been fully explored. Using GPR83/eGFP mice, we show high GPR83 expression on cholinergic interneurons in the nucleus accumbens and moderate expression on ventral tegmental area dopamine neurons. In GPR83 knockout mice, baseline dopamine release in the nucleus accumbens is enhanced which disrupts the ratio of tonic vs phasic release. Additionally, GPR83 knockout leads to changes in the expression of dopamine-related genes. Using the morphine conditioned place preference model, we identify sex differences in morphine reward-learning, show that GPR83 is upregulated in the nucleus accumbens following morphine conditioned place preference, and show that shRNA-mediated knockdown of GPR83 in the nucleus accumbens leads to attenuation morphine reward. Together, these findings detect GPR83 expression in the reward-pathway, and show its involvement in dopamine release and morphine reward-learning.
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Affiliation(s)
- Amanda K Fakira
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, NY, NY, USA
| | - Emily G Peck
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Yutong Liu
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, NY, NY, USA; Nash Family Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, NY, NY, USA
| | - Lindsay M Lueptow
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, NY, NY, USA
| | - Nikita A Trimbake
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, NY, NY, USA
| | - Ming-Hu Han
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, NY, NY, USA; Nash Family Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, NY, NY, USA
| | - Erin S Calipari
- Department of Pharmacology, Vanderbilt Center for Addiction Research, Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Lakshmi A Devi
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, NY, NY, USA; Nash Family Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, NY, NY, USA.
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28
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Bershad AK, Miller MA, Norman GJ, de Wit H. Effects of opioid- and non-opioid analgesics on responses to psychosocial stress in humans. Horm Behav 2018; 102:41-47. [PMID: 29673620 PMCID: PMC6004330 DOI: 10.1016/j.yhbeh.2018.04.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 02/27/2018] [Accepted: 04/13/2018] [Indexed: 12/21/2022]
Abstract
Both preclinical and clinical evidence suggests that the endogenous opioid system is involved in responses to stress. For example, in animal models opioid agonists reduce isolation distress whereas opioid antagonists increase isolation distress. We recently reported that the mixed mu agonist and kappa antagonist buprenorphine dampened responses to acute psychosocial stress in humans. Now we extend this to study the effects of a pure mu-opioid agonist, hydromorphone, and a non-opioid analgesic, acetaminophen, on response to social stress. We compared the effect of hydromorphone (2 and 4 mg), acetaminophen (1000 mg) to a placebo using a between subject design. Healthy adult volunteers were randomly assigned to receive placebo (N = 13), 2 mg hydromorphone (N = 12), 4 mg hydromorphone (N = 12), or 1000 mg acetaminophen (paracetamol; N = 13) under double-blind conditions before undergoing a stress task or a control task on two separate sessions. The stress task, consisting of a standardized speaking task and the non-stressful control task were presented in counterbalanced order. Dependent measures included mood ratings, subjective appraisal of the stress (or no-stress) task, salivary cortisol, pupil diameter, heart rate, and blood pressure. The stress task produced its expected increase in heart rate, blood pressure, salivary cortisol, pupil diameter, and subjective ratings of anxiety and negative mood. Hydromorphone dose-dependently dampened cortisol responses to stress, and decreased ratings of how "challenging" participants found the task. Acetaminophen did not affect physiological responses, but, like hydromorphone, decreased ratings of how "challenging" the task was. The hydromorphone results support the idea that the mu-opioid system is involved in physiological responses to acute stress in humans, in line with results from preclinical studies. The non-opioid analgesic acetaminophen did not dampen physiological responses, but did reduce some components of psychological stress. It remains to be determined how both opioid and non-opioid systems mediate the complex physiological and psychological responses to social stress.
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Affiliation(s)
- Anya K Bershad
- Interdisciplinary Scientist Training Program, University of Chicago, Chicago, IL, USA; Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA
| | - Melissa A Miller
- Interdisciplinary Scientist Training Program, University of Chicago, Chicago, IL, USA
| | - Greg J Norman
- Department of Psychology, University of Chicago, Chicago, IL, USA
| | - Harriet de Wit
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA.
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29
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Legakis LP, Negus SS. Repeated Morphine Produces Sensitization to Reward and Tolerance to Antiallodynia in Male and Female Rats with Chemotherapy-Induced Neuropathy. J Pharmacol Exp Ther 2018; 365:9-19. [PMID: 29363579 DOI: 10.1124/jpet.117.246215] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 01/22/2018] [Indexed: 01/14/2023] Open
Abstract
Paclitaxel is a cancer chemotherapy drug with adverse effects that include chemotherapy-induced neuropathic pain (CINP) as well as depression of behavior and mood. In the clinical setting, opioids are often used concurrently with or after chemotherapy to treat pain related to the cancer or CINP, but repeated opioid exposure can also increase the risk of opioid abuse. In this study, male and female Sprague-Dawley rats were used to test the hypothesis that repeated 3.2-mg/kg doses of morphine would induce tolerance to its antinociceptive effects in a mechanical sensitivity assay and increased expression of its abuse-related rewarding effects in an assay of intracranial self-stimulation (ICSS). Three weeks after four injections of vehicle or 2.0 mg/kg of paclitaxel, the initial morphine dose-effect curves were determined in both assays. Subsequently, rats were treated with 3.2 mg/kg per day morphine for 6 days. On the final day of testing, morphine dose-effect curves were redetermined in both assays. On initial exposure, morphine produced dose-dependent antiallodynia in the assay of mechanical sensitivity, but it produced little or no rewarding effects in the assay of ICSS. After 6 days of repeated treatment, morphine antiallodynia decreased, and morphine reward increased. Females exhibited greater morphine reward on initial exposure than males, but repeated morphine eliminated this sex difference. These results suggest that repeated morphine may produce tolerance to therapeutically beneficial analgesic effects of morphine but increased sensitivity to abuse-related rewarding effects of morphine in subjects treated with paclitaxel.
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Affiliation(s)
- L P Legakis
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia
| | - S S Negus
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia
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30
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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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31
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Alavian F, Ghiasvand S. GABA B receptors within the central nucleus of amygdala may involve in the morphine-induced incentive tolerance in female rats. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2017; 20:822-828. [PMID: 28852448 PMCID: PMC5569599 DOI: 10.22038/ijbms.2017.9018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Objective(s): Central nucleus of amygdala (CeA) is the most important region for morphine-induced reward, and GABAergic system plays an important role on morphine reinforcement. The influence of CeA administration of GABAB receptor agonist and antagonist on the expression and acquisition of morphine-induced incentive tolerance using conditioned place preference (CPP) paradigm was investigated in the present study. Our purpose was to evaluate the role of CeA GABAB receptors in morphine tolerance. Materials and Methods: Seven days after surgery and cannulation, the experiments were begun. Subcutaneous (SC) injections of morphine induced CPP. Administration of one daily dose of morphine (12.5 mg/kg) for 3 days in order to develop tolerance to the drug reduced the conditioning induced by morphine (7.5 mg/kg, SC). GABAB receptor agonist, baclofen (1.5, 6 and 12 µg/rat) or GABAB receptor antagonist, CGP35348 (1.5, 6 and 12 µg/rat) were injected into the CeA 5 min before the experiments in the test day (expression of tolerance) or 5 min before each injection of morphine (12.5 mg/kg) (acquisition of tolerance). Results: It was shown that injections of baclofen (1.5 and 12 µg/rat) reduced acquisition, whereas the dose of 6 µg/rat of the drug exacerbated the acquisition of morphine tolerance. Baclofen at all doses significantly increased the expression of tolerance to morphine. Administration of CGP35348 (1.5, 6 and 12 µg/rat) reduced the acquisition and expression of morphine tolerance. Conclusion: These results confirmed the importance of GABAB receptors with in the CeA in morphine tolerance in female rats.
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Affiliation(s)
- Firoozeh Alavian
- Department of Basic Sciences, Farhangian University, Tehran, Iran
| | - Saeedeh Ghiasvand
- Departments of Biology, Faculty of Science, Malayer University, Malayer, Iran
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32
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Hempel BJ, Wakeford AGP, Nelson KH, Clasen MM, Woloshchuk CJ, Riley AL. An assessment of sex differences in Δ 9-tetrahydrocannabinol (THC) taste and place conditioning. Pharmacol Biochem Behav 2016; 153:69-75. [PMID: 27986515 DOI: 10.1016/j.pbb.2016.11.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 11/28/2016] [Accepted: 11/30/2016] [Indexed: 12/18/2022]
Affiliation(s)
- Briana J Hempel
- Psychopharmacology Laboratory, Center for Behavioral Neuroscience, Department of Psychology, American University, Washington, D.C. 20016, USA.
| | - Alison G P Wakeford
- Psychopharmacology Laboratory, Center for Behavioral Neuroscience, Department of Psychology, American University, Washington, D.C. 20016, USA
| | - Katharine H Nelson
- Psychopharmacology Laboratory, Center for Behavioral Neuroscience, Department of Psychology, American University, Washington, D.C. 20016, USA
| | - Matthew M Clasen
- Psychopharmacology Laboratory, Center for Behavioral Neuroscience, Department of Psychology, American University, Washington, D.C. 20016, USA
| | - Claudia J Woloshchuk
- Psychopharmacology Laboratory, Center for Behavioral Neuroscience, Department of Psychology, American University, Washington, D.C. 20016, USA
| | - Anthony L Riley
- Psychopharmacology Laboratory, Center for Behavioral Neuroscience, Department of Psychology, American University, Washington, D.C. 20016, USA.
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33
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Effects of sex and remifentanil dose on rats' acquisition of responding for a remifentanil-conditioned reinforcer. Behav Pharmacol 2016; 27:137-47. [PMID: 26580131 DOI: 10.1097/fbp.0000000000000205] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Opioid-conditioned reinforcement is thought to exacerbate opioid abuse and dependence. Sex/gender can influence opioid abuse behaviors, but the effects of sex/gender on opioid-conditioned reinforcement, specifically, are unclear. In this study, we compared new-response acquisition with opioid-conditioned reinforcement in male and female rats. First, separate groups received response-independent remifentanil injections (0.0-32.0 μg/kg, intravenous) and presentations of a light-noise stimulus. In the experimental groups, injections and stimulus presentations always co-occurred [paired Pavlovian conditioning (PAV)]; in the control groups, the two occurred independently of each other (random PAV). Next, in the instrumental acquisition (ACQ) sessions, two novel nose-poke manipulanda were introduced. All animals (regardless of sex, dose, and PAV type) could respond in the active nose-poke, which produced the stimulus alone, or in the inactive nose-poke. Both males and females dose-dependently acquired nose-poke responding (active>inactive) after paired PAV, but not after random PAV. Therefore, the stimulus was a conditioned reinforcer. We identified three sex differences. First, only females acquired responding after paired PAV with 32.0 μg/kg remifentanil. Second, using a progressive ratio schedule for ACQ, both sexes acquired responding, but females made significantly more active responses. Third, when a single session of PAV was conducted, only males acquired responding. Thus, rats' sex interacts with pharmacological and environmental factors to determine opioid-conditioned reinforcement.
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34
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Abstract
The purpose of this review is to discuss ways to think about and study sex differences in preclinical animal models. We use the framework of addiction, in which animal models have excellent face and construct validity, to illustrate the importance of considering sex differences. There are four types of sex differences: qualitative, quantitative, population, and mechanistic. A better understanding of the ways males and females can differ will help scientists design experiments to characterize better the presence or absence of sex differences in new phenomena that they are investigating. We have outlined major quantitative, population, and mechanistic sex differences in the addiction domain using a heuristic framework of the three established stages of the addiction cycle: binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation. Female rats, in general, acquire the self-administration of drugs and alcohol more rapidly, escalate their drug taking with extended access more rapidly, show more motivational withdrawal, and (where tested in animal models of "craving") show greater reinstatement. The one exception is that female rats show less motivational withdrawal to alcohol. The bases for these quantitative sex differences appear to be both organizational, in that estradiol-treated neonatal animals show the male phenotype, and activational, in that the female phenotype depends on the effects of gonadal hormones. In animals, differences within the estrous cycle can be observed but are relatively minor. Such hormonal effects seem to be most prevalent during the acquisition of drug taking and less influential once compulsive drug taking is established and are linked largely to progesterone and estradiol. This review emphasizes not only significant differences in the phenotypes of females and males in the domain of addiction but emphasizes the paucity of data to date in our understanding of those differences.
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Affiliation(s)
- Jill B Becker
- Molecular & Behavioral Neuroscience Institute, Department of Psychiatry, Department of Psychology, University of Michigan, Ann Arbor, Michigan (J.B.B.); and Director, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland (G.F.K.)
| | - George F Koob
- Molecular & Behavioral Neuroscience Institute, Department of Psychiatry, Department of Psychology, University of Michigan, Ann Arbor, Michigan (J.B.B.); and Director, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland (G.F.K.)
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Roversi K, Pase CS, Roversi K, Vey LT, Dias VT, Metz VG, Burger ME. Trans fat intake across gestation and lactation increases morphine preference in females but not in male rats: Behavioral and biochemical parameters. Eur J Pharmacol 2016; 788:210-217. [DOI: 10.1016/j.ejphar.2016.06.031] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 06/08/2016] [Accepted: 06/20/2016] [Indexed: 10/21/2022]
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Exposure to morphine-associated cues increases mu opioid receptor mRNA expression in the nucleus accumbens of Wistar Kyoto rats. Behav Brain Res 2016; 313:208-213. [DOI: 10.1016/j.bbr.2016.07.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 06/21/2016] [Accepted: 07/11/2016] [Indexed: 11/22/2022]
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Goulopoulou S, McCarthy CG, Webb RC. Toll-like Receptors in the Vascular System: Sensing the Dangers Within. Pharmacol Rev 2016; 68:142-67. [PMID: 26721702 DOI: 10.1124/pr.114.010090] [Citation(s) in RCA: 170] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Toll-like receptors (TLRs) are components of the innate immune system that respond to exogenous infectious ligands (pathogen-associated molecular patterns, PAMPs) and endogenous molecules that are released during host tissue injury/death (damage-associated molecular patterns, DAMPs). Interaction of TLRs with their ligands leads to activation of downstream signaling pathways that induce an immune response by producing inflammatory cytokines, type I interferons (IFN), and other inflammatory mediators. TLR activation affects vascular function and remodeling, and these molecular events prime antigen-specific adaptive immune responses. Despite the presence of TLRs in vascular cells, the exact mechanisms whereby TLR signaling affects the function of vascular tissues are largely unknown. Cardiovascular diseases are considered chronic inflammatory conditions, and accumulating data show that TLRs and the innate immune system play a determinant role in the initiation and development of cardiovascular diseases. This evidence unfolds a possibility that targeting TLRs and the innate immune system may be a novel therapeutic goal for these conditions. TLR inhibitors and agonists are already in clinical trials for inflammatory conditions such as asthma, cancer, and autoimmune diseases, but their study in the context of cardiovascular diseases is in its infancy. In this article, we review the current knowledge of TLR signaling in the cardiovascular system with an emphasis on atherosclerosis, hypertension, and cerebrovascular injury. Furthermore, we address the therapeutic potential of TLR as pharmacological targets in cardiovascular disease and consider intriguing research questions for future study.
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Affiliation(s)
- Styliani Goulopoulou
- Institute for Cardiovascular and Metabolic Diseases, Department of Obstetrics and Gynecology, University of North Texas Health Science Center, Fort Worth, Texas; and Department of Physiology, Augusta University, Augusta, Georgia
| | - Cameron G McCarthy
- Institute for Cardiovascular and Metabolic Diseases, Department of Obstetrics and Gynecology, University of North Texas Health Science Center, Fort Worth, Texas; and Department of Physiology, Augusta University, Augusta, Georgia
| | - R Clinton Webb
- Institute for Cardiovascular and Metabolic Diseases, Department of Obstetrics and Gynecology, University of North Texas Health Science Center, Fort Worth, Texas; and Department of Physiology, Augusta University, Augusta, Georgia
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Collins D, Reed B, Zhang Y, Kreek MJ. Sex differences in responsiveness to the prescription opioid oxycodone in mice. Pharmacol Biochem Behav 2016; 148:99-105. [PMID: 27316549 DOI: 10.1016/j.pbb.2016.06.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 06/12/2016] [Accepted: 06/13/2016] [Indexed: 11/29/2022]
Abstract
Over-prescription and increased nonmedical use of oxycodone has become a major concern. Despite its increased use, preclinical data concerning oxycodone's effects are still limited, especially in rodent models. To address this, we examined oxycodone's effects on place preference, locomotor activation, corticosterone levels, and thermal analgesia across a range of doses (between 0.3 and 10mg/kg) in gonadally intact, adult male and female C57BL/6J mice. Males and females showed oxycodone-induced conditioned place preference and did not show significant between-sex differences in their place preference behavior. During both CPP conditioning sessions and open field assay, locomotor activity was increased by 1, 3, and 10mg/kg oxycodone in females and by 3 and 10mg/kg oxycodone in males. Plasma corticosterone levels were higher in females (compared to males) at baseline as well as following acute oxycodone injection and open field testing. The time course of oxycodone-induced analgesia was similar in males and females, however the total antinociceptive effect (AUC0-120min) was larger in males compared to females at the highest dose tested (10mg/kg). Taken together, these data suggest that male and female mice are modestly different in their responses to oxycodone.
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Affiliation(s)
- Devon Collins
- The Laboratory of the Biology of Addictive Diseases, The Rockefeller University, 1230 York Avenue, New York, NY 10065, United States.
| | - Brian Reed
- The Laboratory of the Biology of Addictive Diseases, The Rockefeller University, 1230 York Avenue, New York, NY 10065, United States
| | - Yong Zhang
- The Laboratory of the Biology of Addictive Diseases, The Rockefeller University, 1230 York Avenue, New York, NY 10065, United States
| | - Mary Jeanne Kreek
- The Laboratory of the Biology of Addictive Diseases, The Rockefeller University, 1230 York Avenue, New York, NY 10065, United States
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Macúchová E, Ševčíková M, Hrebíčková I, Nohejlová K, Šlamberová R. How various drugs affect anxiety‐related behavior in male and female rats prenatally exposed to methamphetamine. Int J Dev Neurosci 2016; 51:1-11. [DOI: 10.1016/j.ijdevneu.2016.04.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 04/04/2016] [Accepted: 04/07/2016] [Indexed: 01/23/2023] Open
Affiliation(s)
- E. Macúchová
- Charles University in PragueThird Faculty of Medicine, Department of Normal, Pathological and Clinical PhysiologyPragueCzech Republic
| | - M. Ševčíková
- Charles University in PragueThird Faculty of Medicine, Department of Normal, Pathological and Clinical PhysiologyPragueCzech Republic
| | - I. Hrebíčková
- Charles University in PragueThird Faculty of Medicine, Department of Normal, Pathological and Clinical PhysiologyPragueCzech Republic
| | - K. Nohejlová
- Charles University in PragueThird Faculty of Medicine, Department of Normal, Pathological and Clinical PhysiologyPragueCzech Republic
| | - R. Šlamberová
- Charles University in PragueThird Faculty of Medicine, Department of Normal, Pathological and Clinical PhysiologyPragueCzech Republic
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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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Bobzean SAM, DeNobrega AK, Perrotti LI. Sex differences in the neurobiology of drug addiction. Exp Neurol 2014; 259:64-74. [PMID: 24508560 DOI: 10.1016/j.expneurol.2014.01.022] [Citation(s) in RCA: 175] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 01/21/2014] [Accepted: 01/27/2014] [Indexed: 01/09/2023]
Abstract
Epidemiological data demonstrate that while women report lower rates of drug use than men, the number of current drug users and abusers who are women continues to increase. In addition women progress through the phases of addiction differently than men; women transition from casual drug use to addiction faster, are more reactive to stimuli that trigger relapse, and have higher rates of relapse then men. Sex differences in physiological and psychological responses to drugs of abuse are well documented and it is well established that estrogen effects on dopamine (DA) systems are largely responsible for these sex differences. However, the downstream mechanisms that result from interactions between estrogen and the effects of drugs of abuse on the DA system are just beginning to be explored. Here we review the basic neurocircuitry which underlies reward and addiction; highlighting the neuroadaptive changes that occur in the mesolimbic dopamine reward and anti-reward/stress pathways. We propose that sex differences in addiction are due to sex differences in the neural systems which mediate positive and negative reinforcement and that these differences are modulated by ovarian hormones. This forms a neurobehavioral basis for the search for the molecular and cellular underpinnings that uniquely guide motivational behaviors and make women more vulnerable to developing and sustaining addiction than men.
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Affiliation(s)
- Samara A M Bobzean
- Department of Psychology, College of Science, The University of Texas at Arlington, Arlington, TX 76019, USA
| | - Aliza K DeNobrega
- Department of Psychology, College of Science, The University of Texas at Arlington, Arlington, TX 76019, USA
| | - Linda I Perrotti
- Department of Psychology, College of Science, The University of Texas at Arlington, Arlington, TX 76019, USA.
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Lin HC, Chang YP, Wang PW, Wu HC, Yen CN, Yeh YC, Chung KS, Chang HC, Yen CF. Gender differences in heroin users receiving methadone maintenance therapy in Taiwan. J Addict Dis 2013; 32:140-9. [PMID: 23815421 DOI: 10.1080/10550887.2013.795466] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
This study examined gender differences in heroin users who first received MMT. Compared with men, female heroin users were younger and more likely to be unemployed, to have family members using illicit substances, to initiate heroin use at a younger age, to begin MMT earlier after starting heroin use, to have methamphetamine use, to initiate methamphetamine use at a younger age, and to report a child-raising burden and a prior history of traumatic experiences. Men were more likely to have use of betel quid, and to initiate alcohol, nicotine and betel quid use at a younger age than women.
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Affiliation(s)
- Huang-Chi Lin
- Department of Psychiatry, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
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Kosten TA, Shen XY, O'Malley PW, Kinsey BM, Lykissa ED, Orson FM, Kosten TR. A morphine conjugate vaccine attenuates the behavioral effects of morphine in rats. Prog Neuropsychopharmacol Biol Psychiatry 2013; 45:223-9. [PMID: 23739535 PMCID: PMC3773503 DOI: 10.1016/j.pnpbp.2013.05.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Revised: 05/04/2013] [Accepted: 05/22/2013] [Indexed: 11/27/2022]
Abstract
Vaccines for opioid dependence may provide a treatment that would reduce or slow the distribution of the drug to brain, thus reducing the drug's reinforcing effects. We tested whether a conjugate vaccine against morphine (keyhole limpet hemocyanin-6-succinylmorphine; KLH-6-SM) administered to rats would produce antibodies and show specificity for morphine or other heroin metabolites. The functional effects of the vaccine were tested with antinociceptive and conditioned place preference (CPP) tests. Rats were either vaccinated with KLH-6-SM and received two boosts 3 and 16 weeks later or served as controls and received KLH alone. Anti-morphine antibodies were produced in vaccinated rats; levels increased and were sustained at moderate levels through 24 weeks. Antibody binding was inhibited by free morphine and other heroin metabolites as demonstrated by competitive inhibition ELISA. Vaccinated rats showed reduced morphine CPP, tested during weeks 4 to 6, and decreased antinociceptive responses to morphine, tested at week 7. Brain morphine levels, assessed using gas-chromatography coupled to mass spectrometry (GC-MS) on samples obtained at 26 weeks, were significantly lower in vaccinated rats. This suggests that morphine entry into the brain was reduced or slowed. These results provide support for KLH-6-SM as a candidate vaccine for opioid dependence.
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Affiliation(s)
- Therese A. Kosten
- Immunology Allergy & Rheumatology, Department of Medicine, Baylor College of Medicine, Houston, TX, United States,Corresponding author at: Menninger Department of Psychiatry and Behavioral Sciences, 2002 Holcombe Blvd., Houston, TX 77030, United States. Tel: +1 713 794 7637; fax: +1 713 794 7240
| | - Xiaoyun Y. Shen
- Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, Houston, TX, United States,Immunology Allergy & Rheumatology, Department of Medicine, Baylor College of Medicine, Houston, TX, United States
| | - Patrick W. O'Malley
- Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, Houston, TX, United States
| | - Berma M. Kinsey
- Immunology Allergy & Rheumatology, Department of Medicine, Baylor College of Medicine, Houston, TX, United States
| | | | - Frank M. Orson
- Immunology Allergy & Rheumatology, Department of Medicine, Baylor College of Medicine, Houston, TX, United States,The Michael E Debakey Veteran's Medical Affairs Center, Houston, TX, United States
| | - Thomas R. Kosten
- Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, Houston, TX, United States,The Michael E Debakey Veteran's Medical Affairs Center, Houston, TX, United States
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Pedrón VT, Taravini IR, Induni AS, Balerio GN. Baclofen did not modify sexually dimorphic c-Fos expression during morphine withdrawal syndrome. Synapse 2012; 67:118-26. [DOI: 10.1002/syn.21620] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Accepted: 10/26/2012] [Indexed: 12/18/2022]
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Langleben DD, Busch EL, O'Brien CP, Elman I. Depot naltrexone decreases rewarding properties of sugar in patients with opioid dependence. Psychopharmacology (Berl) 2012; 220:559-64. [PMID: 21960180 PMCID: PMC3302938 DOI: 10.1007/s00213-011-2503-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Accepted: 09/12/2011] [Indexed: 11/25/2022]
Abstract
BACKGROUND Opioid neurotransmission mediates hedonic value of sweet tastants; their intake may be exaggerated by the consumption of exogenous opioids (e.g., opioid dependence). Sweet Taste Test (STT) is a validated quantitative instrument assessing taste perception and hedonic features of sugar (sucrose) using a randomized and double-blind administration at five different sucrose concentrations ranging from 0.05 to 0.83 M. METHODS The STT and cue-induced craving procedure were administered to opioid-dependent patients (n = 15) before and 1 week after the injection of a long-acting depot naltrexone (XRNT) preparation. RESULTS Analyses of covariance, employing sucrose concentration and its perceived taste as covariates, showed that XRNT therapy significantly reduced the self-reported hedonic and motivational characteristics of sucrose. Greater reductions in both these characteristics were associated with more diminution in the cue-induced opioid craving. CONCLUSIONS Opioid antagonism in opioid-dependent subjects leads to a smaller sweet taste reward, which, in turn, may be proportional to decreased opioid craving. These pilot results support the heuristic value of the STT as a potential marker of the XRNT treatment response and call for further inquiry into potential clinical applications of the test.
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Affiliation(s)
- Daniel D Langleben
- Department of Psychiatry, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.
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Gender Differences in Depression: Assessing Mediational Effects of Overt Behaviors and Environmental Reward through Daily Diary Monitoring. DEPRESSION RESEARCH AND TREATMENT 2012; 2012:865679. [PMID: 22454769 PMCID: PMC3290799 DOI: 10.1155/2012/865679] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Accepted: 12/04/2011] [Indexed: 11/18/2022]
Abstract
Gender differences in the prevalence of depression are well documented. To further explore the relation between gender and depression, this study used daily diaries to examine gender differences within thirteen behavioral domains and whether differential frequency of overt behaviors and environmental reward mediated the relationship between gender and depression severity. The sample included 82 undergraduate students [66% females; 84% Caucasian; Mean age = 20.2 years]. Overall, females engaged in a significantly greater breadth of behavioral domains and reported a higher level of environmental reward. Females spent more time in the domains of health/hygiene, spiritual activities, and eating with others. Males spent more time in the domains of physical activity, sexual activity, and hobbies and recreational experiences. Females found social activities, passive/sedentary behaviors, eating with others, and engagement in "other" activities more rewarding. Gender had a significant direct effect on depression severity, with females reporting increased depression. This effect was attenuated by the mediator (total environmental reward) such that to the extent females exhibited increased environmental reward, the gender effect on depression was attenuated. These data support behavioral models of depression, indicate increased reinforcement sensitivity among females, and have clinical relevance in the context of assessment and behavioral activation interventions for depression.
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Role of gonadal hormones on mu-opioid-stimulated [³⁵S]GTPγS binding and morphine-mediated antinociception in male and female Sprague-Dawley rats. Psychopharmacology (Berl) 2011; 218:483-92. [PMID: 21607564 DOI: 10.1007/s00213-011-2335-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Accepted: 04/29/2011] [Indexed: 12/23/2022]
Abstract
RATIONALE Male rats are more sensitive to morphine-mediated antinociception than female rats. A role for gonadal hormones in this sex difference has not been clearly defined. OBJECTIVES To test the hypothesis that in vivo manipulation of gonadal hormones alters morphine-mediated G protein activation and leads to changes in morphine-mediated antinociception. METHODS Adult male and female rats were gonadectomized and treated with either estradiol or testosterone in the females or testosterone in the male for up to 10 days. The ability of morphine and the peptidic mu-opioid agonist [D-Ala(2), N-MePhe(4), Gly-ol]-enkephalin (DAMGO) to stimulate [(35)S]GTPγS binding was measured in brain slices. In separate groups of identically treated rats, the antinociceptive response to morphine was determined using the warm-water tail-withdrawal assay. RESULTS In the thalamus, morphine- and DAMGO-stimulated [(35)S]GTPγS binding was reduced by estradiol treatment of gonadectomized females compared to gonadectomized females treated with vehicle or testosterone. In the nucleus accumbens, the morphine-stimulated [(35)S]GTPγS binding was increased by estradiol treatment of gonadectomized females. In males, castration caused an increase in agonist-stimulated binding in the thalamus and a reduction in the amygdala compared with intact males. No significant changes were seen in mu-opioid agonist-stimulated [(35)S]GTPγS binding in other brain regions. There was no difference in antinociception following the systemic administration of morphine across the different hormonal manipulation conditions and the greater sensitivity of males was maintained irrespective of the treatment conditions. CONCLUSIONS The modulation of mu-opioid receptor activation of G proteins by manipulation of sex hormones is region-specific and not reflected in antinociceptive responsiveness to morphine.
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Arzate DM, Portillo W, Rodríguez C, Corona R, Paredes RG. Extended paced mating tests induces conditioned place preference without affecting sexual arousal. Horm Behav 2011; 59:674-80. [PMID: 20816964 DOI: 10.1016/j.yhbeh.2010.08.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Accepted: 08/25/2010] [Indexed: 11/18/2022]
Abstract
One way to evaluate sexual arousal is by measuring approach behavior to sexual incentive stimuli. In our case we measure approach behavior to an originally non-preferred compartment which is associated with the physiological state induced by mating. This change of preference indicative of a positive affective (reward) state can be evaluated by conditioned place preference (CPP). We have shown that the CPP induced by paced mating is mediated by opioids. The administration of opioids also induces a reward state. The present study was designed to compare the rewarding properties of paced mating and a morphine injection. One group of females was allowed to pace the sexual interaction before being placed in the non-preferred compartment. In alternate sessions they received a morphine injection before being placed in the preferred compartment. In another group of females, the treatments were reversed. Only the females placed in the originally non-preferred compartment after paced mating changed their original preference, suggesting that paced mating induces a positive affective, reward, state of higher intensity than a morphine injection of 1mg/kg. In a second experiment we determined if females allowed to pace the sexual interaction for 1h would still developed CPP. No change in preference was observed in the females that mated for 1h without pacing the sexual interaction. On the other hand, females that received between 10 and 15 paced intromissions as well as females that paced the sexual interaction for 1h developed a clear CPP. The second experiment demonstrated that pacing is rewarding even in an extended mating session in which the females received around 25 intromissions and several ejaculations. These results further demonstrate the biological relevance associated with the ability of the female to space coital stimulation received during mating. This positive affective state will contribute to increase sexual arousal the next time a rat finds an appropriate mate.
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Affiliation(s)
- Dulce Ma Arzate
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, México
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Hao Y, Huang W, Nielsen DA, Kosten TA. Litter gender composition and sex affect maternal behavior and DNA methylation levels of the oprm1 gene in rat offspring. Front Psychiatry 2011; 2:21. [PMID: 21629839 PMCID: PMC3098712 DOI: 10.3389/fpsyt.2011.00021] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Accepted: 04/12/2011] [Indexed: 01/05/2023] Open
Abstract
The mu-opioid receptor is encoded by the Oprm1 gene and contributes to mother-infant behaviors. Rodent dams lick male pups more than female pups in the anogenital region. This behavior is linked to stress responsivity in the offspring that may be mediated by epigenetic changes. We hypothesized that maternal behavior may affect DNA methylation levels of the Oprm1 gene and show sex differences. To further explore sex differences in mother-pup behaviors and DNA methylation levels, we altered the litter gender composition (LGC) of rats. Litters were culled to eight all male, all female, or four male/four female pups on postnatal (PN) day 1. On PN4, 7, and 10, a dam was placed in a test cage with a pup for a 10-min period. Latency to pup contact was determined as were times spent licking the anogenital and other body regions of the pup. Frequencies of other behaviors were tabulated. On PN35, samples from various brain regions were obtained. DNA methylation at specific CpG sites in the Oprm1 promoter region were measured by direct sequencing of bisulfite-treated DNA. LGC and sex interacted with day for latency to pup contact. Latencies were longest on PN4 for single-sex males and on PN10 for single-sex females. Dams licked male pups more than female pups in both the anogenital and other body areas. Sex differences were seen in other behaviors. LGC altered DNA methylation at specific CpG's of Oprm1 in hippocampus with higher levels in single-sex rats. In nucleus accumbens, single-sex males showed hypermethylation levels, a trend seen in caudate-putamen. Results confirm and extend sex differences in maternal care with modest LGC effects. That both LGC and sex have enduring effects on DNA methylation of the Oprm1 gene in brain regions associated with addiction, stress regulation, motivation, and cognition may suggest one factor that contributes to gender differences in these behaviors.
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Affiliation(s)
- Yanli Hao
- Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine Houston, TX, USA
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Bajic D, Commons KG. Acute noxious stimulation modifies morphine effect in serotonergic but not dopaminergic midbrain areas. Neuroscience 2010; 166:720-9. [PMID: 20026253 PMCID: PMC2823975 DOI: 10.1016/j.neuroscience.2009.12.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Revised: 11/18/2009] [Accepted: 12/11/2009] [Indexed: 11/20/2022]
Abstract
It is poorly understood if and how pain may modify the effect of opioids on neural systems that contribute to reward and addictive behavior. We hypothesized that the activation of ascending dopaminergic and serotonergic nuclei by morphine is modified by the presence of noxious stimulation. Immunohistochemical double-labeling technique with Fos was used to examine if an intraplantar formalin injection, an acute noxious input, changed the effect of morphine on dopaminergic neurons of the ventral tegmental area (VTA), and serotonergic neurons of the dorsal raphe nucleus (DR). Four groups of rats were analyzed: (1) control injected with normal saline s.c., (2) rats treated with formalin into the hind paw 30 min after normal saline injection, (3) rats injected with morphine sulfate s.c., and (4) rats treated with formalin into the hind paw 30 min after morphine injection (morphine/formalin). Following morphine injection, there was an increase in the number of dopaminergic neurons in the VTA with Fos immunolabeling. However, noxious stimulation did not detectably change morphine's effect on Fos expression in VTA dopamine neurons. In contrast, the number of serotonergic neurons containing Fos was increased in the morphine/formalin group compared to all other groups and this effect was topographically selective for the dorsal area of the DR at mid rostro-caudal levels. Therefore, morphine's activation of the VTA, which is associated with motivated behavior and reward seeking, appears similar in the context of pain. However, activation of the ascending serotonin system, which influences mood and has the capacity to modify reward pathways, appears different. In addition, these findings reveal interactions between nociceptive signaling and opioids that contrasts with the notion that opioids simply block access of nociceptive signaling to supraspinal structures.
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Affiliation(s)
- D Bajic
- Department of Anesthesiology, Perioperative and Pain Medicine, Children's Hospital Boston, Boston, MA, USA.
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