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Etaee F, Rezvani-Kamran A, Komaki S, Asadbegi M, Faraji N, Raoufi S, Taheri M, Kourosh-Arami M, Komaki A. Effects of Buprenorphine on the Memory and Learning Deficit Induced by Methamphetamine Administration in Male Rats. Front Behav Neurosci 2021; 15:748563. [PMID: 34887733 PMCID: PMC8650604 DOI: 10.3389/fnbeh.2021.748563] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 10/29/2021] [Indexed: 11/23/2022] Open
Abstract
Little is known about the effects of methamphetamine (Meth) and buprenorphine (Bup) on memory and learning in rats. The aim of this investigation was to examine the impact of Meth and Bup on memory and learning. Fourteen male Wistar rats weighing 250–300 g were assigned to four groups: Sham, Meth, Bup, and Meth + Bup and were treated for 1 week. Spatial learning and memory, avoidance learning, and locomotion were assessed using the Morris water maze, passive avoidance learning, and open field tests, respectively. Meth and Bup impaired spatial learning and memory in rats. Co-administration of Meth + Bup did not increase the time spent in the target quadrant compared to Meth alone in the MWM. The Bup and Meh + Bup groups were found with an increase in step-through latency (STLr) and a decrease in the time spent in the dark compartment (TDC). Meth and Bup had no effects on locomotor activity in the open field test. Bup showed a beneficial effect on aversive memory. Since Bup demonstrates fewer side effects than other opioid drugs, it may be preferable for the treatment of avoidance memory deficits in patients with Meth addiction.
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Affiliation(s)
- Farshid Etaee
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.,Department of Internal Medicine, Texas Tech University Health Sciences Center, Amarillo, TX, United States
| | - Arezoo Rezvani-Kamran
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Somayeh Komaki
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Masoumeh Asadbegi
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Nafiseh Faraji
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Safoura Raoufi
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Mohammad Taheri
- Skull Base Research Center, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Masoumeh Kourosh-Arami
- Department of Neuroscience, School of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Alireza Komaki
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
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Gulick D, Gamsby JJ. Racing the clock: The role of circadian rhythmicity in addiction across the lifespan. Pharmacol Ther 2018; 188:124-139. [PMID: 29551440 DOI: 10.1016/j.pharmthera.2018.03.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Although potent effects of psychoactive drugs on circadian rhythms were first described over 30 years ago, research into the reciprocal relationship between the reward system and the circadian system - and the impact of this relationship on addiction - has only become a focus in the last decade. Nonetheless, great progress has been made in that short time toward understanding how drugs of abuse impact the molecular and physiological circadian clocks, as well as how disruption of normal circadian rhythm biology may contribute to addiction and ameliorate the efficacy of treatments for addiction. In particular, data have emerged demonstrating that disrupted circadian rhythms, such as those observed in shift workers and adolescents, increase susceptibility to addiction. Furthermore, circadian rhythms and addiction impact one another longitudinally - specifically from adolescence to the elderly. In this review, the current understanding of how the circadian clock interacts with substances of abuse within the context of age-dependent changes in rhythmicity, including the potential existence of a drug-sensitive clock, the correlation between chronotype and addiction vulnerability, and the importance of rhythmicity in the mesocorticolimbic dopamine system, is discussed. The primary focus is on alcohol addiction, as the preponderance of research is in this area, with references to other addictions as warranted. The implications of clock-drug interactions for the treatment of addiction will also be reviewed, and the potential of therapeutics that reset the circadian rhythm will be highlighted.
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Affiliation(s)
- Danielle Gulick
- Byrd Alzheimer's Institute, University of South Florida Health, Tampa, FL, USA; Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, USA.
| | - Joshua J Gamsby
- Byrd Alzheimer's Institute, University of South Florida Health, Tampa, FL, USA; Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
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Avila JA, Zanca RM, Shor D, Paleologos N, Alliger AA, Figueiredo-Pereira ME, Serrano PA. Chronic voluntary oral methamphetamine induces deficits in spatial learning and hippocampal protein kinase Mzeta with enhanced astrogliosis and cyclooxygenase-2 levels. Heliyon 2018; 4:e00509. [PMID: 29560440 PMCID: PMC5857642 DOI: 10.1016/j.heliyon.2018.e00509] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 12/29/2017] [Accepted: 01/08/2018] [Indexed: 12/26/2022] Open
Abstract
Methamphetamine (MA) is an addictive drug with neurotoxic effects on the brain producing cognitive impairment and increasing the risk for neurodegenerative disease. Research has focused largely on examining the neurochemical and behavioral deficits induced by injecting relatively high doses of MA [30 mg/kg of body weight (bw)] identifying the upper limits of MA-induced neurotoxicity. Accordingly, we have developed an appetitive mouse model of voluntary oral MA administration (VOMA) based on the consumption of a palatable sweetened oatmeal mash containing a known amount of MA. This VOMA model is useful for determining the lower limits necessary to produce neurotoxicity in the short-term and long-term as it progresses over time. We show that mice consumed on average 1.743 mg/kg bw/hour during 3 hours, and an average of 5.23 mg/kg bw/day over 28 consecutive days on a VOMA schedule. Since this consumption rate is much lower than the neurotoxic doses typically injected, we assessed the effects of long-term chronic VOMA on both spatial memory performance and on the levels of neurotoxicity in the hippocampus. Following 28 days of VOMA, mice exhibited a significant deficit in short-term spatial working memory and spatial reference learning on the radial 8-arm maze (RAM) compared to controls. This was accompanied by a significant decrease in memory markers protein kinase Mzeta (PKMζ), calcium impermeable AMPA receptor subunit GluA2, and the post-synaptic density 95 (PSD-95) protein in the hippocampus. Compared to controls, the VOMA paradigm also induced decreases in hippocampal levels of dopamine transporter (DAT) and tyrosine hydroxylase (TH), as well as increases in dopamine 1 receptor (D1R), glial fibrillary acidic protein (GFAP) and cyclooxygenase-2 (COX-2), with a decrease in prostaglandins E2 (PGE2) and D2 (PGD2). These results demonstrate that chronic VOMA reaching 146 mg/kg bw/28d induces significant hippocampal neurotoxicity. Future studies will evaluate the progression of this neurotoxic state.
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Affiliation(s)
- Jorge A. Avila
- Department of Psychology, Hunter College, City University of New York, New York, NY, USA
- The Graduate Center of CUNY, New York, NY, USA
| | - Roseanna M. Zanca
- Department of Psychology, Hunter College, City University of New York, New York, NY, USA
- The Graduate Center of CUNY, New York, NY, USA
| | - Denis Shor
- Department of Psychology, Hunter College, City University of New York, New York, NY, USA
| | - Nicholas Paleologos
- Department of Psychology, Hunter College, City University of New York, New York, NY, USA
| | - Amber A. Alliger
- Department of Psychology, Hunter College, City University of New York, New York, NY, USA
| | - Maria E. Figueiredo-Pereira
- Department of Biological Sciences, Hunter College, City University of New York, New York, NY, USA
- The Graduate Center of CUNY, New York, NY, USA
| | - Peter A. Serrano
- Department of Psychology, Hunter College, City University of New York, New York, NY, USA
- The Graduate Center of CUNY, New York, NY, USA
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Trim9 Deletion Alters the Morphogenesis of Developing and Adult-Born Hippocampal Neurons and Impairs Spatial Learning and Memory. J Neurosci 2017; 36:4940-58. [PMID: 27147649 DOI: 10.1523/jneurosci.3876-15.2016] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 03/07/2016] [Indexed: 12/30/2022] Open
Abstract
UNLABELLED During hippocampal development, newly born neurons migrate to appropriate destinations, extend axons, and ramify dendritic arbors to establish functional circuitry. These developmental stages are recapitulated in the dentate gyrus of the adult hippocampus, where neurons are continuously generated and subsequently incorporate into existing, local circuitry. Here we demonstrate that the E3 ubiquitin ligase TRIM9 regulates these developmental stages in embryonic and adult-born mouse hippocampal neurons in vitro and in vivo Embryonic hippocampal and adult-born dentate granule neurons lacking Trim9 exhibit several morphological defects, including excessive dendritic arborization. Although gross anatomy of the hippocampus was not detectably altered by Trim9 deletion, a significant number of Trim9(-/-) adult-born dentate neurons localized inappropriately. These morphological and localization defects of hippocampal neurons in Trim9(-/-) mice were associated with extreme deficits in spatial learning and memory, suggesting that TRIM9-directed neuronal morphogenesis may be involved in hippocampal-dependent behaviors. SIGNIFICANCE STATEMENT Appropriate generation and incorporation of adult-born neurons in the dentate gyrus are critical for spatial learning and memory and other hippocampal functions. Here we identify the brain-enriched E3 ubiquitin ligase TRIM9 as a novel regulator of embryonic and adult hippocampal neuron shape acquisition and hippocampal-dependent behaviors. Genetic deletion of Trim9 elevated dendritic arborization of hippocampal neurons in vitro and in vivo Adult-born dentate granule cells lacking Trim9 similarly exhibited excessive dendritic arborization and mislocalization of cell bodies in vivo These cellular defects were associated with severe deficits in spatial learning and memory.
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Huckans M, Wilhelm CJ, Phillips TJ, Huang ET, Hudson R, Loftis JM. Parallel Effects of Methamphetamine on Anxiety and CCL3 in Humans and a Genetic Mouse Model of High Methamphetamine Intake. Neuropsychobiology 2017; 75:169-177. [PMID: 29402784 PMCID: PMC5911417 DOI: 10.1159/000485129] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 11/08/2017] [Indexed: 12/20/2022]
Abstract
BACKGROUND Methamphetamine (MA) abuse causes immune dysfunction and neuropsychiatric impairment. The mechanisms underlying these deficits remain unidentified. METHODS The effects of MA on anxiety-like behavior and immune function were investigated in mice selectively bred to voluntarily consume high amounts of MA [i.e., MA high drinking (MAHDR) mice]. MA (or saline) was administered to mice using a chronic (14-day), binge-like model. Performance in the elevated zero maze (EZM) was determined 5 days after the last MA dose to examine anxiety-like behavior. Cytokine and chemokine expressions were measured in the hippocampus using quantitative polymerase chain reaction (qPCR). Human studies were also conducted to evaluate symptoms of anxiety using the General Anxiety Disorder-7 Scale in adults with and without a history of MA dependence. Plasma samples collected from human research participants were used for confirmatory analysis of murine qPCR results using an enzyme-linked immunosorbent assay. RESULTS During early remission from MA, MAHDR mice exhibited increased anxiety-like behavior on the EZM and reduced expression of chemokine (C-C motif) ligand 3 (ccl3) in the hippocampus relative to saline-treated mice. Human adults actively dependent on MA and those in early remission had elevated symptoms of anxiety as well as reductions in plasma levels of CCL3, relative to adults with no history of MA abuse. CONCLUSIONS The results highlight the complex effects of MA on immune and behavioral function and suggest that alterations in CCL3 signaling may contribute to the mood impairments observed during remission from MA addiction.
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Affiliation(s)
- Marilyn Huckans
- Research and Development Service, VA Portland Health Care System, Portland, OR, USA,Department of Psychiatry, Oregon Health and Science University, Portland, OR, USA,Mental Health and Clinical Neurosciences Division, VA Portland Health Care System, Portland, OR, USA,Methamphetamine Abuse Research Center, Oregon Health and Science University, Portland, OR, USA
| | - Clare J. Wilhelm
- Research and Development Service, VA Portland Health Care System, Portland, OR, USA,Department of Psychiatry, Oregon Health and Science University, Portland, OR, USA
| | - Tamara J. Phillips
- Research and Development Service, VA Portland Health Care System, Portland, OR, USA,Methamphetamine Abuse Research Center, Oregon Health and Science University, Portland, OR, USA,Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, USA
| | - Elaine T. Huang
- Research and Development Service, VA Portland Health Care System, Portland, OR, USA,Methamphetamine Abuse Research Center, Oregon Health and Science University, Portland, OR, USA
| | - Rebekah Hudson
- Research and Development Service, VA Portland Health Care System, Portland, OR, USA
| | - Jennifer M. Loftis
- Research and Development Service, VA Portland Health Care System, Portland, OR, USA,Department of Psychiatry, Oregon Health and Science University, Portland, OR, USA,Methamphetamine Abuse Research Center, Oregon Health and Science University, Portland, OR, USA
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Phillips TJ, Mootz JRK, Reed C. Identification of Treatment Targets in a Genetic Mouse Model of Voluntary Methamphetamine Drinking. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2016; 126:39-85. [PMID: 27055611 DOI: 10.1016/bs.irn.2016.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Methamphetamine has powerful stimulant and euphoric effects that are experienced as rewarding and encourage use. Methamphetamine addiction is associated with debilitating illnesses, destroyed relationships, child neglect, violence, and crime; but after many years of research, broadly effective medications have not been identified. Individual differences that may impact not only risk for developing a methamphetamine use disorder but also affect treatment response have not been fully considered. Human studies have identified candidate genes that may be relevant, but lack of control over drug history, the common use or coabuse of multiple addictive drugs, and restrictions on the types of data that can be collected in humans are barriers to progress. To overcome some of these issues, a genetic animal model comprised of lines of mice selectively bred for high and low voluntary methamphetamine intake was developed to identify risk and protective alleles for methamphetamine consumption, and identify therapeutic targets. The mu opioid receptor gene was supported as a target for genes within a top-ranked transcription factor network associated with level of methamphetamine intake. In addition, mice that consume high levels of methamphetamine were found to possess a nonfunctional form of the trace amine-associated receptor 1 (TAAR1). The Taar1 gene is within a mouse chromosome 10 quantitative trait locus for methamphetamine consumption, and TAAR1 function determines sensitivity to aversive effects of methamphetamine that may curb intake. The genes, gene interaction partners, and protein products identified in this genetic mouse model represent treatment target candidates for methamphetamine addiction.
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Affiliation(s)
- T J Phillips
- Methamphetamine Abuse Research Center, Oregon Health & Science University, Portland, OR, United States; Veterans Affairs Portland Health Care System, Portland, OR, United States.
| | - J R K Mootz
- Methamphetamine Abuse Research Center, Oregon Health & Science University, Portland, OR, United States
| | - C Reed
- Methamphetamine Abuse Research Center, Oregon Health & Science University, Portland, OR, United States
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Lominac KD, Quadir SG, Barrett HM, McKenna CL, Schwartz LM, Ruiz PN, Wroten MG, Campbell RR, Miller BW, Holloway JJ, Travis KO, Rajasekar G, Maliniak D, Thompson AB, Urman LE, Kippin TE, Phillips TJ, Szumlinski KK. Prefrontal glutamate correlates of methamphetamine sensitization and preference. Eur J Neurosci 2016; 43:689-702. [PMID: 26742098 DOI: 10.1111/ejn.13159] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 12/16/2015] [Accepted: 12/17/2015] [Indexed: 12/28/2022]
Abstract
Methamphetamine (MA) is a widely misused, highly addictive psychostimulant that elicits pronounced deficits in neurocognitive function related to hypo-functioning of the prefrontal cortex (PFC). Our understanding of how repeated MA impacts excitatory glutamatergic transmission within the PFC is limited, as is information about the relationship between PFC glutamate and addiction vulnerability/resiliency. In vivo microdialysis and immunoblotting studies characterized the effects of MA (ten injections of 2 mg/kg, i.p.) upon extracellular glutamate in C57BL/6J mice and upon glutamate receptor and transporter expression, within the medial PFC. Glutamatergic correlates of both genetic and idiopathic variance in MA preference/intake were determined through studies of high vs. low MA-drinking selectively bred mouse lines (MAHDR vs. MALDR, respectively) and inbred C57BL/6J mice exhibiting spontaneously divergent place-conditioning phenotypes. Repeated MA sensitized drug-induced glutamate release and lowered indices of N-methyl-d-aspartate receptor expression in C57BL/6J mice, but did not alter basal extracellular glutamate content or total protein expression of Homer proteins, or metabotropic or α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid glutamate receptors. Elevated basal glutamate, blunted MA-induced glutamate release and ERK activation, as well as reduced protein expression of mGlu2/3 and Homer2a/b were all correlated biochemical traits of selection for high vs. low MA drinking, and Homer2a/b levels were inversely correlated with the motivational valence of MA in C57BL/6J mice. These data provide novel evidence that repeated, low-dose MA is sufficient to perturb pre- and post-synaptic aspects of glutamate transmission within the medial PFC and that glutamate anomalies within this region may contribute to both genetic and idiopathic variance in MA addiction vulnerability/resiliency.
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Affiliation(s)
- Kevin D Lominac
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Sema G Quadir
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Hannah M Barrett
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Courtney L McKenna
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Lisa M Schwartz
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Paige N Ruiz
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Melissa G Wroten
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Rianne R Campbell
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Bailey W Miller
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - John J Holloway
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Katherine O Travis
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Ganesh Rajasekar
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Dan Maliniak
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Andrew B Thompson
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Lawrence E Urman
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Tod E Kippin
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
| | - Tamara J Phillips
- Behavioral Neuroscience and Methamphetamine Abuse Research Center, VA Portland Health Care System, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Karen K Szumlinski
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, CA, 93106-9660, USA
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Zuloaga DG, Iancu OD, Weber S, Etzel D, Marzulla T, Stewart B, Allen CN, Raber J. Enhanced functional connectivity involving the ventromedial hypothalamus following methamphetamine exposure. Front Neurosci 2015; 9:326. [PMID: 26441501 PMCID: PMC4585047 DOI: 10.3389/fnins.2015.00326] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 08/31/2015] [Indexed: 11/13/2022] Open
Abstract
Methamphetamine (MA) consumption causes disruption of many biological rhythms including the sleep-wake cycle. This circadian effect is seen shortly following MA exposure and later in life following developmental MA exposure. MA phase shifts, entrains the circadian clock and can also alter the entraining effect of light by currently unknown mechanisms. We analyzed and compared immunoreactivity of the immediate early gene c-Fos, a marker of neuronal activity, to assess neuronal activation 2 h following MA exposure in the light and dark phases. We used network analyses of correlation patterns derived from global brain immunoreactivity patterns of c-Fos, to infer functional connectivity between brain regions. There were five distinct patterns of neuronal activation. In several brain areas, neuronal activation following exposure to MA was stronger in the light than the dark phase, highlighting the importance of considering circadian periods of increased effects of MA in defining experimental conditions and understanding the mechanisms underlying detrimental effects of MA exposure to brain function. Functional connectivity between the ventromedial hypothalamus (VMH) and other brain areas, including the paraventricular nucleus of the hypothalamus and basolateral and medial amygdala, was enhanced following MA exposure, suggesting a role for the VMH in the effects of MA on the brain.
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Affiliation(s)
- Damian G Zuloaga
- Department of Behavioral Neuroscience, Oregon Health & Science University Portland Portland, OR, USA ; Department of Psychology, University at Albany Albany, NY, USA
| | - Ovidiu D Iancu
- Department of Behavioral Neuroscience, Oregon Health & Science University Portland Portland, OR, USA
| | - Sydney Weber
- Department of Behavioral Neuroscience, Oregon Health & Science University Portland Portland, OR, USA
| | - Desiree Etzel
- Department of Behavioral Neuroscience, Oregon Health & Science University Portland Portland, OR, USA
| | - Tessa Marzulla
- Department of Behavioral Neuroscience, Oregon Health & Science University Portland Portland, OR, USA
| | - Blair Stewart
- Department of Behavioral Neuroscience, Oregon Health & Science University Portland Portland, OR, USA
| | - Charles N Allen
- Department of Behavioral Neuroscience, Oregon Health & Science University Portland Portland, OR, USA ; Oregon Institute of Occupational Health Sciences, Oregon Health & Science University Portland Portland, OR, USA
| | - Jacob Raber
- Department of Behavioral Neuroscience, Oregon Health & Science University Portland Portland, OR, USA ; Department of Neurology, Oregon Health & Science University Portland Portland, OR, USA ; Department of Radiation Medicine, Oregon Health & Science University Portland Portland, OR, USA ; Division of Neuroscience, ONPRC, Oregon Health & Science University Portland Portland, OR, USA
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Phillips TJ, Shabani S. An animal model of differential genetic risk for methamphetamine intake. Front Neurosci 2015; 9:327. [PMID: 26441502 PMCID: PMC4585292 DOI: 10.3389/fnins.2015.00327] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 08/31/2015] [Indexed: 11/13/2022] Open
Abstract
The question of whether genetic factors contribute to risk for methamphetamine (MA) use and dependence has not been intensively investigated. Compared to human populations, genetic animal models offer the advantages of control over genetic family history and drug exposure. Using selective breeding, we created lines of mice that differ in genetic risk for voluntary MA intake and identified the chromosomal addresses of contributory genes. A quantitative trait locus was identified on chromosome 10 that accounts for more than 50% of the genetic variance in MA intake in the selected mouse lines. In addition, behavioral and physiological screening identified differences corresponding with risk for MA intake that have generated hypotheses that are testable in humans. Heightened sensitivity to aversive and certain physiological effects of MA, such as MA-induced reduction in body temperature, are hallmarks of mice bred for low MA intake. Furthermore, unlike MA-avoiding mice, MA-preferring mice are sensitive to rewarding and reinforcing MA effects, and to MA-induced increases in brain extracellular dopamine levels. Gene expression analyses implicate the importance of a network enriched in transcription factor genes, some of which regulate the mu opioid receptor gene, Oprm1, in risk for MA use. Neuroimmune factors appear to play a role in differential response to MA between the mice bred for high and low intake. In addition, chromosome 10 candidate gene studies provide strong support for a trace amine-associated receptor 1 gene, Taar1, polymorphism in risk for MA intake. MA is a trace amine-associated receptor 1 (TAAR1) agonist, and a non-functional Taar1 allele segregates with high MA consumption. Thus, reduced TAAR1 function has the potential to increase risk for MA use. Overall, existing findings support the MA drinking lines as a powerful model for identifying genetic factors involved in determining risk for harmful MA use. Future directions include the development of a binge model of MA intake, examining the effect of withdrawal from chronic MA on MA intake, and studying potential Taar1 gene × gene and gene × environment interactions. These and other studies are intended to improve our genetic model with regard to its translational value to human addiction.
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Affiliation(s)
- Tamara J Phillips
- VA Portland Health Care System Portland, OR, USA ; Department of Behavioral Neuroscience and Methamphetamine Abuse Research Center, Oregon Health & Science University Portland, OR, USA
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