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Li X, Slesinger PA. GABA B Receptors and Drug Addiction: Psychostimulants and Other Drugs of Abuse. Curr Top Behav Neurosci 2020; 52:119-155. [PMID: 33442842 DOI: 10.1007/7854_2020_187] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Metabotropic GABAB receptors (GABABRs) mediate slow inhibition and modulate synaptic plasticity throughout the brain. Dysfunction of GABABRs has been associated with psychiatric illnesses and addiction. Drugs of abuse alter GABAB receptor (GABABR) signaling in multiple brain regions, which partly contributes to the development of drug addiction. Recently, GABABR ligands and positive allosteric modulators (PAMs) have been shown to attenuate the initial rewarding effect of addictive substances, inhibit seeking and taking of these drugs, and in some cases, ameliorate drug withdrawal symptoms. The majority of the anti-addiction effects seen with GABABR modulation can be localized to ventral tegmental area (VTA) dopamine neurons, which receive complex inhibitory and excitatory inputs that are modified by drugs of abuse. Preclinical research suggests that GABABR PAMs are emerging as promising candidates for the treatment of drug addiction. Clinical studies on drug dependence have shown positive results with GABABR ligands but more are needed, and compounds with better pharmacokinetics and fewer side effects are critically needed.
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Affiliation(s)
- Xiaofan Li
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| | - Paul A Slesinger
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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2
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Nguyen T, Li GE, Chen H, Cranfield CG, McGrath KC, Gorrie CA. Neurological Effects in the Offspring After Switching From Tobacco Cigarettes to E-Cigarettes During Pregnancy in a Mouse Model. Toxicol Sci 2019; 172:191-200. [PMID: 31505003 DOI: 10.1093/toxsci/kfz194] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 07/25/2019] [Accepted: 08/17/2019] [Indexed: 12/17/2022] Open
Abstract
Abstract
Maternal smoking is currently a public health concern and has been associated with a number of complications in the offspring. E-cigarettes are gaining popularity as a “safer” alternative to tobacco cigarettes during pregnancy, however, there are a limited number of studies to suggest that it is actually “safe.” Balb/C female mice were exposed to ambient air (n = 8; Sham), or tobacco cigarette smoke (n = 8; SE) before gestation, during gestation and lactation. A third group was exposed to cigarette smoke before gestation followed by e-cigarette aerosols during gestation and lactation (n = 8; Switch). Male offspring (12-week old, n = 10–14/group) underwent behavioral assessments to investigate short-term memory, anxiety, and activity using the novel object recognition and elevated plus maze tests. Brains were collected at postnatal day (P)1, P20, and Week 13 for global DNA methylation, epigenetic gene expression, and neuronal cell counts. The offspring from mothers switching to e-cigarettes exhibited no change in exploration/activity but showed a decrease in global DNA methylation, Aurora Kinase (Aurk) A and AurkB gene expression and a reduction in neuronal cell numbers in the cornu ammonis 1 region of the dorsal hippocampus compared with the SE group. Continuous tobacco cigarette smoke exposure during pregnancy resulted in marked neurological deficits in the offspring. Switching to e-cigarettes during pregnancy reduced these neurological deficits compared with cigarette smoke exposure. However, neurological changes were still observed, so we therefore conclude that e-cigarette use during pregnancy is not advised.
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Affiliation(s)
- Tara Nguyen
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Sydney, New South Wales 2007, Australia
| | - Gerard E Li
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Sydney, New South Wales 2007, Australia
| | - Hui Chen
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Sydney, New South Wales 2007, Australia
| | - Charles G Cranfield
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Sydney, New South Wales 2007, Australia
| | - Kristine C McGrath
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Sydney, New South Wales 2007, Australia
| | - Catherine A Gorrie
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Sydney, New South Wales 2007, Australia
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3
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Alasmari F, Crotty Alexander LE, Hammad AM, Bojanowski CM, Moshensky A, Sari Y. Effects of Chronic Inhalation of Electronic Cigarette Vapor Containing Nicotine on Neurotransmitters in the Frontal Cortex and Striatum of C57BL/6 Mice. Front Pharmacol 2019; 10:885. [PMID: 31456684 PMCID: PMC6699083 DOI: 10.3389/fphar.2019.00885] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 07/15/2019] [Indexed: 12/12/2022] Open
Abstract
Electronic (E)-cigarettes are the latest form of nicotine delivery device and are highly popular in the general population. It is currently unknown whether vaping E-cigarettes (E-CIGs) leads to nicotine addiction. Alterations in the levels of the neurotransmitters in the mesocorticolimbic areas have been reported to mediate the initiation and development of nicotine addiction. Therefore, to determine whether E-CIGs activate the same addiction pathways as conventional cigarettes, we investigated for the effects of daily inhalation of nicotine (24 mg/ml)-containing E-CIG vapor for 6 months on the concentrations of these neurotransmitters in the frontal cortex (FC) and striatum (STR) of male C57BL/6 mice as compared to control group that was exposed to air only. We reported here that 6-month E-CIG vapor containing nicotine inhalation decreased dopamine concentration only in the STR. There were no changes in serotonin concentrations in the FC or STR. Chronic E-CIG exposure also increased glutamate concentration in the STR alone, while glutamine concentrations were increased in both the FC and STR. We found that E-CIG exposure also decreased GABA concentration only in the FC. These data suggest that chronic E-CIG use alters homeostasis of several neurotransmitters in the mesocorticolimbic areas, which may result in the development of nicotine dependence in E-CIG users.
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Affiliation(s)
- Fawaz Alasmari
- Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH, United States.,Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Laura E Crotty Alexander
- Pulmonary and Critical Care Section, VA San Diego Healthcare System, San Diego, CA, United States.,Department of Medicine, Division of Pulmonary and Critical Care, University of California at San Diego (UCSD), La Jolla, CA, United States
| | - Alaa M Hammad
- Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH, United States.,Department of Pharmacy, College of Pharmacy, Al-Zaytoonah University of Jordan, Amman, Jordan
| | - Christine M Bojanowski
- Pulmonary and Critical Care Section, VA San Diego Healthcare System, San Diego, CA, United States.,Department of Medicine, Division of Pulmonary and Critical Care, University of California at San Diego (UCSD), La Jolla, CA, United States
| | - Alex Moshensky
- Pulmonary and Critical Care Section, VA San Diego Healthcare System, San Diego, CA, United States.,Department of Medicine, Division of Pulmonary and Critical Care, University of California at San Diego (UCSD), La Jolla, CA, United States
| | - Youssef Sari
- Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH, United States
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4
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Abstract
Introduction: Smoking is the main preventable cause of lung cancer. This review summarizes preclinical and clinical data on the mechanisms of smoking-associated cancer development of the major histological lung cancer types small cell lung carcinoma squamous cell carcinoma and pulmonary adenocarcinoma (PAC) and the impact of several factors other than smoking on this process. Areas covered: The role of intracellular signaling induced by nicotinic receptors and beta-adrenergic receptors, the resulting increase in intracellular cyclic adenosine monophosphate (cAMP) as a key driver of PAC and the promoting effects of respiratory tract diseases and their therapeutics, psychological stress and global warming. Expert opinion: Smoking has deleterious effects on the regulation of lung epithelia by neurotransmitter receptors that are further enhanced by gene mutations. Sensitization of the alpha-7 nicotinic receptor (α7nAChR) by COPD enhances the carcinogenic effects of smoking and turns nicotine into a carcinogen. Nicotine vaping may, therefore, cause cancer in individuals with chronic obstructive pulmonary disease. The opposing effects of cAMP on the major lung cancer types indicate that patients with PAC of Clara cell phenotype (PAC-Cl) will benefit from treatment with cAMP reducers and suggest that global warming-induced respiratory tract diseases and their therapeutics cause the global increase in the incidence of PAC.
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Affiliation(s)
- Hildegard M Schuller
- a Department of Biomedical & Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee , Knoxville , TN , USA
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5
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Winckelmans E, Vrijens K, Tsamou M, Janssen BG, Saenen ND, Roels HA, Kleinjans J, Lefebvre W, Vanpoucke C, de Kok TM, Nawrot TS. Newborn sex-specific transcriptome signatures and gestational exposure to fine particles: findings from the ENVIRONAGE birth cohort. Environ Health 2017; 16:52. [PMID: 28583124 PMCID: PMC5458481 DOI: 10.1186/s12940-017-0264-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 05/22/2017] [Indexed: 05/14/2023]
Abstract
BACKGROUND Air pollution exposure during pregnancy has been associated with adverse birth outcomes and health problems later in life. We investigated sex-specific transcriptomic responses to gestational long- and short-term exposure to particulate matter with a diameter < 2.5 μm (PM2.5) in order to elucidate potential underlying mechanisms of action. METHODS Whole genome gene expression was investigated in cord blood of 142 mother-newborn pairs that were enrolled in the ENVIRONAGE birth cohort. Daily PM2.5 exposure levels were calculated for each mother's home address using a spatial-temporal interpolation model in combination with a dispersion model to estimate both long- (annual average before delivery) and short- (last month of pregnancy) term exposure. We explored the association between gene expression levels and PM2.5 exposure, and identified modulated pathways by overrepresentation analysis and gene set enrichment analysis. RESULTS Some processes were altered in both sexes for long- (e.g. DNA damage) or short-term exposure (e.g. olfactory signaling). For long-term exposure in boys neurodevelopment and RhoA pathways were modulated, while in girls defensin expression was down-regulated. For short-term exposure we identified pathways related to synaptic transmission and mitochondrial function (boys) and immune response (girls). CONCLUSIONS This is the first whole genome gene expression study in cord blood to identify sex-specific pathways altered by PM2.5. The identified transcriptome pathways could provide new molecular insights as to the interaction pattern of early life PM2.5 exposure with the biological development of the fetus.
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Affiliation(s)
- Ellen Winckelmans
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
| | - Karen Vrijens
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
| | - Maria Tsamou
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
| | - Bram G. Janssen
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
| | - Nelly D. Saenen
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
| | - Harry A. Roels
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
- Louvain Centre for Toxicology and Applied Pharmacology (LTAP), Université catholique de Louvain, Brussels, Belgium
| | - Jos Kleinjans
- Department of Toxicogenomics, Maastricht University, Maastricht, The Netherlands
| | - Wouter Lefebvre
- Environmental Risk and Health, Flemish Institute for Technical Research (VITO), Mol, Belgium
| | | | - Theo M. de Kok
- Department of Toxicogenomics, Maastricht University, Maastricht, The Netherlands
| | - Tim S. Nawrot
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
- Department of Public Health & Primary Care, Leuven University, Kapucijnenvoer 35, 3000 Leuven, Belgium
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6
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Neal RE, Jagadapillai R, Chen J, Webb C, Stocke K, Greene RM, Pisano MM. Developmental cigarette smoke exposure II: Hippocampus proteome and metabolome profiles in adult offspring. Reprod Toxicol 2016; 65:436-447. [PMID: 27208486 DOI: 10.1016/j.reprotox.2016.05.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 05/05/2016] [Accepted: 05/13/2016] [Indexed: 11/27/2022]
Abstract
Exposure to cigarette smoke during development is linked to neurodevelopmental delays and cognitive impairment including impulsivity, attention deficit disorder, and lower IQ. Utilizing a murine experimental model of "active" inhalation exposure to cigarette smoke spanning the entirety of gestation and through human third trimester equivalent hippocampal development [gestation day 1 (GD1) through postnatal day 21 (PD21)], we examined hippocampus proteome and metabolome alterations present at a time during which developmental cigarette smoke exposure (CSE)-induced behavioral and cognitive impairments are evident in adult animals from this model system. At six month of age, carbohydrate metabolism and lipid content in the hippocampus of adult offspring remained impacted by prior exposure to cigarette smoke during the critical period of hippocampal ontogenesis indicating limited glycolysis. These findings indicate developmental CSE-induced systemic glucose availability may limit both organism growth and developmental trajectory, including the capacity for learning and memory.
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Affiliation(s)
- Rachel E Neal
- Department of Environmental and Occupational Health Sciences, School of Public Health and Information Sciences, University of Louisville, Louisville, KY, USA; Birth Defects Center, University of Louisville, Louisville, KY, USA.
| | - Rekha Jagadapillai
- Department of Molecular, Cellular, and Craniofacial Biology, ULSD, University of Louisville, Louisville, KY, USA
| | - Jing Chen
- Department of Environmental and Occupational Health Sciences, School of Public Health and Information Sciences, University of Louisville, Louisville, KY, USA
| | - Cindy Webb
- Department of Molecular, Cellular, and Craniofacial Biology, ULSD, University of Louisville, Louisville, KY, USA
| | - Kendall Stocke
- Department of Environmental and Occupational Health Sciences, School of Public Health and Information Sciences, University of Louisville, Louisville, KY, USA
| | - Robert M Greene
- Department of Molecular, Cellular, and Craniofacial Biology, ULSD, University of Louisville, Louisville, KY, USA; Birth Defects Center, University of Louisville, Louisville, KY, USA
| | - M Michele Pisano
- Department of Molecular, Cellular, and Craniofacial Biology, ULSD, University of Louisville, Louisville, KY, USA; Birth Defects Center, University of Louisville, Louisville, KY, USA
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7
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Amos-Kroohs RM, Williams MT, Braun AA, Graham DL, Webb CL, Birtles TS, Greene RM, Vorhees CV, Pisano MM. Neurobehavioral phenotype of C57BL/6J mice prenatally and neonatally exposed to cigarette smoke. Neurotoxicol Teratol 2013; 35:34-45. [PMID: 23314114 DOI: 10.1016/j.ntt.2013.01.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Revised: 12/18/2012] [Accepted: 01/02/2013] [Indexed: 12/26/2022]
Abstract
Although maternal cigarette smoking during pregnancy is a well-documented risk factor for a variety of adverse pregnancy outcomes, how prenatal cigarette smoke exposure affects postnatal neurobehavioral/cognitive development remains poorly defined. In order to investigate the cause of an altered behavioral phenotype, mice developmentally exposed to a paradigm of 'active' maternal cigarette smoke is needed. Accordingly, cigarette smoke exposed (CSE) and air-exposed C57BL/6J mice were treated for 6h per day in paired inhalation chambers throughout gestation and lactation and were tested for neurobehavioral effects while controlling for litter effects. CSE mice exhibited less than normal anxiety in the elevated zero maze, transient hypoactivity during a 1h locomotor activity test, had longer latencies on the last day of cued Morris water maze testing, impaired hidden platform learning in the Morris water maze during acquisition, reversal, and shift trials, and impaired retention for platform location on probe trials after reversal but not after acquisition or shift. CSE mice also showed a sexually dimorphic response in central zone locomotion to a methamphetamine challenge (males under-responded and females over-responded), and showed reduced anxiety in the light-dark test by spending more time on the light side. No differences on tests of marble burying, acoustic startle response with prepulse inhibition, Cincinnati water maze, matching-to-sample Morris water maze, conditioned fear, forced swim, or MK-801-induced locomotor activation were found. Collectively, the data indicate that developmental cigarette smoke exposure induces subnormal anxiety in a novel environment, impairs spatial learning and reference memory while sparing other behaviors (route-based learning, fear conditioning, and forced swim immobility). The findings add support to mounting evidence that developmental cigarette smoke exposure has long-term adverse effects on brain function.
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Affiliation(s)
- Robyn M Amos-Kroohs
- Department of Pediatrics, Division of Child Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039, United States
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8
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Repeated administration of the GABAB receptor positive modulator BHF177 decreased nicotine self-administration, and acute administration decreased cue-induced reinstatement of nicotine seeking in rats. Psychopharmacology (Berl) 2011; 215:117-28. [PMID: 21181127 PMCID: PMC3072487 DOI: 10.1007/s00213-010-2119-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2010] [Accepted: 11/26/2010] [Indexed: 11/22/2022]
Abstract
RATIONALE γ-Aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the brain and is implicated in the modulation of central reward processes. Acute or chronic administration of GABA(B) receptor agonists or positive modulators decreased self-administration of various drugs of abuse. Furthermore, GABA(B) receptor agonists inhibited cue-induced reinstatement of nicotine- and cocaine-seeking behavior. Because of their fewer adverse side effects compared with GABA(B) receptor agonists, GABA(B) receptor positive modulators are potentially improved therapeutic compounds for the treatment of drug dependence compared with agonists. OBJECTIVES AND METHODS We examined whether the acute effects of the GABA(B) receptor positive modulator N-[(1R,2R,4S)-bicyclo[2.2.1]hept-2-yl]-2-methyl-5-[4-(trifluoromethyl)phenyl]-4-pyrimidinamine (BHF177) on nicotine self-administration and food-maintained responding under a fixed-ratio 5 schedule of reinforcement were maintained after repeated administration. The effects of acute BHF177 administration on cue-induced nicotine- and food-seeking behavior, a putative animal model of relapse, were also examined. RESULTS Repeated administration of BHF177 for 14 days decreased nicotine self-administration, with small tolerance observed during the last 7 days of treatment, whereas BHF177 minimally affected food-maintained responding. Acute BHF177 administration dose-dependently blocked cue-induced reinstatement of nicotine-, but not food-, seeking behavior after a 10-day extinction period. CONCLUSIONS These results showed that BHF177 selectively blocked nicotine self-administration and prevented cue-induced reinstatement of nicotine seeking, with minimal effects on responding for food and no effect on cue-induced reinstatement of food seeking. Thus, GABA(B) receptor positive modulators could be useful therapeutics for the treatment of different aspects of nicotine dependence by facilitating smoking cessation by decreasing nicotine intake and preventing relapse to smoking in humans.
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9
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Naseer MI, Lee HY, Kim MO. Neuroprotective effect of vitamin C against the ethanol and nicotine modulation of GABA(B) receptor and PKA-alpha expression in prenatal rat brain. Synapse 2010; 64:467-77. [PMID: 20175221 DOI: 10.1002/syn.20752] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Prenatal ethanol exposure has various deleterious effects on neuronal development and can induce various defects in developing brain, resulting in fetal alcohol syndrome (FAS). gamma-Aminobutyric acid (GABA(B)) receptor (R) is known to play an important role during the development of the central nervous system (CNS). Our study was designed to investigate the effect of ethanol (100 mM), nicotine (50 microM) (for 30 min and 1 h), vitamin C (vitC, 0.5 mM), ethanol plus vitC, and nicotine plus vitC on expression level of GABA(B1), GABA(B2)R, and protein kinase A-alpha (PKA) in prenatal rat cortical and hippocampal neurons at gestational days (GD) 17.5. The results showed that, upon ethanol and nicotine exposure, GABA(B1) and GABA(B2)R protein expression increased significantly in the cortex and hippocampus for a short (30 min) and long term (1 h), whereas only GABA(B2)R subunit was decreased upon nicotine exposure for a long term in the cortex. Furthermore, PKA expression in cortex and hippocampus increased with ethanol exposure during short term, whereas long-term exposure results increased in cortex and decreased in hippocampus. Moreover, the cotreatment of vitC with ethanol and nicotine showed significantly decreased expression of GABA(B1), GABA(B2)R, and PKA in cortex and hippocampus for a long-term exposure. Mitochondrial membrane potential, Fluoro-jade-B, and propidium iodide staining were used to elucidate possible neurodegeneration. Our results suggest the involvement of GABA(B)R and PKA in nicotine and ethanol-mediated neurodevelopmental defects and the potential use of vitC as a effective protective agent for FAS-related deficits.
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Affiliation(s)
- M I Naseer
- Division of Life Science, College of Natural Sciences and Applied Life Science (Brain Korea 21), Gyeongsang National University, Chinju 660-701, South Korea
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10
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Abstract
Cigarette smoking is the main preventable cause of death in developed countries, and the development of more effective treatments is necessary. Cumulating evidence suggests that cognitive enhancement may contribute to the addictive actions of nicotine. Several studies have demonstrated that nicotine enhances cognitive performance in both smokers and non-smokers. Genetic studies support the role of both dopamine (DA) and nicotinic acetylcholine receptors (nAChRs) associated with nicotine-induced cognitive enhancement. Based on knockout mice studies, beta2 nAChRs are thought to be essential in mediating the cognitive effects of nicotine. alpha7nAChRs are associated with attentional and sensory filtering response, especially in schizophrenic individuals. Genetic variation in D2 type DA receptors and the catechol-O-methyltransferase enzyme appears to moderate cognitive deficits induced by smoking abstinence. Serotonin transporter (5-HTT) gene variation also moderates nicotine-induced improvement in spatial working memory. Less is known about the contribution of genetic variation in DA transporter and D4 type DA receptor genetic variation on the cognitive effects of nicotine. Future research will provide a clearer understanding of the mechanism underlying the cognitive-enhancing actions of nicotine.
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Affiliation(s)
- Aryeh I Herman
- Department of Psychiatry and VA Connecticut Healthcare System, School of Medicine, Yale University, West Haven, CT 06516, USA
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11
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Naha N, Lee HY, Hwang JS, Bahk JY, Park MS, Lee SY, Kim SH, Kim MO. Nicotine tolerance to PC12 cell line: acute and chronic exposures modulate dopamine D2 receptor and tyrosine hydroxylase expression. Neurol Res 2009; 31:289-99. [PMID: 19406037 DOI: 10.1179/174313209x382403] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
PC12 is a clonal cell line from chromaffin tumor of rat adrenal pheochromocytoma that releases catecholamine including dopamine, which via interaction with its receptor (D(1) and D(2) receptor), is known to be involved in reward and reinforcement properties of many addictive drugs like nicotine. Nicotine tolerance is the key aspect of nicotine addiction. However, nicotine tolerance on dopamine receptors in PC12 cell line is poorly understood. In this paper, we have demonstrated the tolerance to acute and chronic nicotine administrations on PC12 cell line on the basis of the expressions of dopamine receptors and tyrosine hydroxylase, the rate-limiting enzyme of dopamine biosynthesis, by Western blot, immunohistochemistry and in situ hybridization. In vitro treatment of nicotine resulted in similar expressional changes of dopamine D(2) receptor and tyrosine hydroxylase at protein and mRNA levels in dose- and time-dependent manner, whereas dopamine D(1) receptor did not reveal any positive output. Moreover, moderate to strong signals were obtained from 0.1 to 10 microM of nicotine concentrations and the signals were gradually decreased at 100 and 1000 microM nicotine concentrations relative to the untreated control cell line. Therefore, this study implied a new approach towards nicotine tolerance which is likely to be related to the modulation of dopamine D(2) receptor and tyrosine hydroxylase expressions by chronic and acute nicotine exposures in PC12 cell line.
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Affiliation(s)
- Nibedita Naha
- Division of Life Science, Applied Life Science (Brain Korea 21 and EB-NCRC), Gyeongsang National University, Jinju 660-701, South Korea
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12
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Cellular events in nicotine addiction. Semin Cell Dev Biol 2009; 20:418-31. [PMID: 19560047 DOI: 10.1016/j.semcdb.2009.01.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2008] [Revised: 12/19/2008] [Accepted: 01/09/2009] [Indexed: 11/23/2022]
Abstract
In the 25 years since the observation that chronic exposure to nicotine could regulate the number and function of high affinity nicotine binding sites in the brain there has been a major effort to link alterations in nicotinic acetylcholine receptors (nAChRs) to nicotine-induced behaviors that drive the addiction to tobacco products. Here we review the proposed roles of various nAChR subtypes in the addiction process, with emphasis on how they are regulated by nicotine and the implications for understanding the cellular neurobiology of addiction to this drug.
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13
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Dunckley T, Lukas RJ. Nicotinic modulation of gene expression in SH-SY5Y neuroblastoma cells. Brain Res 2006; 1116:39-49. [PMID: 16949557 DOI: 10.1016/j.brainres.2006.07.111] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2005] [Revised: 07/24/2006] [Accepted: 07/29/2006] [Indexed: 11/28/2022]
Abstract
Exposure to nicotine has a broad range of physiological and psychological effects that can be long lasting and contribute to nicotine dependence. On a time course longer than that needed to activate nicotinic acetylcholine receptor (nAChR) function, nicotine exposure induces functional inactivation of nAChR, upregulation of nAChR radioligand binding sites, and other alterations of cellular functions. To identify possible mechanisms underlying nicotine-induced changes in nAChR numbers and function, we defined changes in gene expression in neuron-like, SH-SY5Y human neuroblastoma cells following 24 h of continuous exposure to 1 mM nicotine. This treatment condition produces both functional inactivation and upregulation of nAChR. Repeat and cross-controlled microarray ( approximately 5000 genes queried) analyses revealed 163 genes whose expression was consistently altered at the p<0.01 level following nicotine treatment. Quantitative, real-time, reverse transcription-polymerase chain reaction analyses confirmed altered expression of thirteen out of fourteen of these genes chosen for further study, including contactin 1, myozenin 2, and ubiquitin-conjugating enzymes E2C and E2S. Inhibition or reversal of these effects by the general nAChR antagonist, d-tubocurarine, indicated that gene expression changes are dependent on nAChR activation. Studies using other nAChR subtype-selective antagonists identified gene expression changes that required activation of both alpha7- and alpha3*-nAChR, alpha7-nAChR alone, or either alpha7- or alpha3beta4*-nAChR, suggesting some convergent and some divergent pathways of gene activation coupled to these nAChR subtypes. These results suggest that longer-term physiological and psychological effects of nicotine exposure and changes in nAChR expression may be due in part to effects on gene expression initiated by interactions with nAChR.
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Affiliation(s)
- Travis Dunckley
- Division of Neurobiology, Barrow, Neurological Institute, 350 West Thomas Road, Phoenix, AZ 85013, USA
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14
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Paterson NE, Bruijnzeel AW, Kenny PJ, Wright CD, Froestl W, Markou A. Prolonged nicotine exposure does not alter GABAB receptor-mediated regulation of brain reward function. Neuropharmacology 2005; 49:953-62. [PMID: 16005474 DOI: 10.1016/j.neuropharm.2005.04.031] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2004] [Revised: 04/01/2005] [Accepted: 04/29/2005] [Indexed: 11/25/2022]
Abstract
Gamma-aminobutyric acid subtype B (GABA(B)) receptors play an important role in regulating brain reward function. Accumulating evidence suggests that chronic exposure to drugs of abuse may alter GABA(B) receptor function. The present studies investigated whether chronic nicotine administration, using a regimen that induces nicotine dependence, increased inhibitory regulation of brain reward function by GABA(B) receptors, as measured by intracranial self-stimulation (ICSS) thresholds in rats. Such an action of nicotine may contribute to the reward deficit observed during nicotine withdrawal. Nicotine-dependent and control rats received the GABA transaminase inhibitor gamma-vinyl-GABA or the GABA(B) receptor agonist CGP44532 according to a within-subjects Latin square design, and ICSS thresholds were assessed post-injection. Systemic administration of the lowest doses of GVG or CGP44532 did not alter reward thresholds in control or nicotine-treated rats, whereas the highest doses of each drug elevated thresholds similarly in both groups. Further, micro-infusion of CGP44532 directly into the ventral tegmental area elevated ICSS thresholds similarly in saline- and nicotine-treated rats. Overall, these data demonstrate that prolonged nicotine exposure did not alter GABA(B) receptor-mediated regulation of brain reward function, and suggest that alterations in GABA(B) receptor activity are unlikely to play a role in the brain reward deficits associated with spontaneous nicotine withdrawal.
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Affiliation(s)
- Neil E Paterson
- Department of Molecular and Integrative Neuroscience, CVN-7, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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15
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Li SP, Park MS, Jin GZ, Kim JH, Lee HL, Lee YL, Kim JH, Bahk JY, Park TJ, Koh PO, Chung BC, Kim MO. Ethanol modulates GABA(B) receptor expression in cortex and hippocampus of the adult rat brain. Brain Res 2005; 1061:27-35. [PMID: 16246313 DOI: 10.1016/j.brainres.2005.08.052] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2005] [Revised: 08/24/2005] [Accepted: 08/29/2005] [Indexed: 01/15/2023]
Abstract
Using in situ hybridization, RNase protection assay and Western blot, we studied the effects of ethanol on the expression levels of GABA(B) receptor mRNA and protein in the cortex and hippocampus from adult rat brain. The results showed that ethanol significantly increased GABA(B1) and GABA(B2) receptor protein expression in the cortex, whereas only GABA(B2) was increased in the hippocampus. GABA(B) receptor agonist baclofen could partially reverse the effect of ethanol. Further studies of the mRNA levels defined that GABA(B1) mRNA levels were significantly increased in the hippocampus, with no significant changes of GABA(B2) mRNA levels. Moreover, GABA(B1) and GABA(B2) receptor mRNA levels were increased on 3-week ethanol treatment. Finally, GABA(B) agonist baclofen and antagonist phaclofen showed significant decreasing effects on GABA(B1) receptor mRNA levels in the cortex, but not in the hippocampus. These results were further confirmed by in situ hybridization. Thus, the present results showed the effects of ethanol on GABA(B) receptors in the cortex and hippocampus, implying the possible role of GABA(B) receptor in ethanol effects. The effects of GABA(B) receptor agonist and antagonist suggested that the possible mechanisms underlying that GABA(B) receptor modulated the behavioral effect induced by ethanol.
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Affiliation(s)
- Shu Peng Li
- Division of Life Science and Applied Life Science (Brain Korea 21), Gyeongsang National University, Chinju 660-701, South Korea
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16
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Enna SJ, Bowery NG. GABA(B) receptor alterations as indicators of physiological and pharmacological function. Biochem Pharmacol 2005; 68:1541-8. [PMID: 15451397 DOI: 10.1016/j.bcp.2004.06.037] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2004] [Accepted: 06/21/2004] [Indexed: 11/15/2022]
Abstract
Given the widespread distribution of GABA(B) receptors throughout the central nervous system, and within certain peripheral organs, it is likely their selective pharmacological manipulation could be of benefit in the treatment of a variety of disorders. Studies aimed at defining the clinical potential of GABA(B) receptor agonists and antagonists have included gene deletion experiments, examination of changes in receptor binding, subunit expression and function in diseased tissue, as well as after the chronic administration of drugs. The results indicate that a functional GABA(B) receptor requires the combination of GABA(B(1)) and GABA(B(2)) subunits, that receptor function does not always correlate with subunit expression and receptor binding, and that GABA(B) receptor modifications may be associated with the clinical response to antidepressants, mood stabilizers, and GABA(B) receptor agonists and antagonists. Moreover, changes in GABA(B) binding or expression suggest this receptor may be involved in mediating symptoms associated with chronic pain, epilepsy and schizophrenia. This, together with results from other types of studies, indicates the potential therapeutic value of developing drugs capable of selectively activating, inhibiting, or modulating GABA(B) receptor function.
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Affiliation(s)
- S J Enna
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical School, 3901 Rainbow Boulevard, Mail Stop 1018, Kansas City, Kansas 66160-0227, USA.
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17
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Abstract
Dependence on tobacco is one of the most important health problems in our society due to the direct relationship with lung cancer. Early studies in twins revealed that genetic factors modify the susceptibility to develop tobacco dependence. Different studies are underway to try to find an association between polymorphisms of genes involved either in nicotine metabolization or in neural transmission and the initiation and maintenance of the dependence on tobacco. Here we review the studies performed so far and discuss new perspectives for future studies.
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Affiliation(s)
- Miguel Barrueco
- Servicio de Neumología, Hospital Universitario de Salamanca, Salamanca, Spain
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18
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Li SP, Kim JH, Park MS, Bahk JY, Chung BC, Kim MO. Ethanol modulates the expression of GABAB receptor mRNAs in the prenatal rat brain in an age and area dependent manner. Neuroscience 2005; 134:857-66. [PMID: 16054771 DOI: 10.1016/j.neuroscience.2005.05.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2005] [Revised: 05/04/2005] [Accepted: 05/05/2005] [Indexed: 10/25/2022]
Abstract
Prenatal ethanol exposure has various deleterious effects on neuronal development. As GABA(B) receptor is known to play an important role during the development of the CNS, we now focused on its mRNA expression pattern in the rat brain during the late gestational days (GD) from 15.5 to GD 21.5. Ethanol's effect was also observed from GD 11.5 to GD 21.5. GABA(B1) receptor mRNA showed a high expression level in GD 15.5 and 19.5, while GABA(B2) receptor mRNA did in GD 15.5 and 21.5. The mRNAs levels depended on age and area during development. Ethanol exposure decreased GABA(B1) receptor from GD 11.5 to GD 19.5 with slight increases in GD 21.5. The decreasing effects were area dependent, with the highest effects in the forebrain including cortex, whereas slight effects were observed in the midbrain and hindbrain. The present results suggest an important role of GABA(B) receptor in the effects of ethanol on prenatal brain developmental processes.
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Affiliation(s)
- S P Li
- Division of Life Science, College of Natural Sciences and Applied Life Science (Brain Korea 21), Gyeongsang National University, Gyeongnam, Chinju, 660-701, South Korea
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19
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Paterson NE, Froestl W, Markou A. Repeated administration of the GABAB receptor agonist CGP44532 decreased nicotine self-administration, and acute administration decreased cue-induced reinstatement of nicotine-seeking in rats. Neuropsychopharmacology 2005; 30:119-28. [PMID: 15266350 DOI: 10.1038/sj.npp.1300524] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Acute administration of gamma-aminobutyric acid B (GABAB) receptor agonists decreased nicotine, cocaine, ethanol, and heroin self-administration. GABAB receptor agonists also decreased cue-induced cocaine craving or seeking in humans and animals, respectively. The present study investigated the effects of repeated subcutaneous administration of the GABAB receptor agonist CGP44532 on nicotine- and food-maintained responding under a fixed ratio 5 schedule of reinforcement. The second part of the study determined whether contingent presentation of previously nicotine-associated cues reinstated extinguished nicotine-seeking behavior, and whether acute subcutaneous CGP44532 administration affected cue-induced reinstatement of extinguished nicotine-seeking behavior. The results indicated that repeated administration of 0.25 mg/kg CGP44532 selectively decreased nicotine self-administration compared to food-maintained responding during the first 7 days of treatment. Repeated administration of 0.5 mg/kg/day CGP44532 nonselectively decreased both nicotine- and food-maintained responding. Contingent presentation of previously nicotine-associated cues reinstated extinguished nicotine-seeking behavior. Further, acute CGP44532 administration (0.125 and 0.25 mg/kg) decreased cue-induced reinstatement of nicotine-seeking behavior. In summary, the present results indicated that 0.25 mg/kg/day CGP44532 selectively decreased nicotine self-administration compared to food-maintained responding, and acute administration of CGP44532 (0.125 and 0.25 mg/kg) dose-dependently decreased cue-induced reinstatement of nicotine-seeking behavior.
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Affiliation(s)
- Neil E Paterson
- Department of Neuropharmacology, The Scripps Research Institute, La Jolla, CA 92037, USA
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20
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Levin ED, Weber E, Icenogle L. Baclofen interactions with nicotine in rats: effects on memory. Pharmacol Biochem Behav 2004; 79:343-8. [PMID: 15501311 DOI: 10.1016/j.pbb.2004.08.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2004] [Revised: 07/28/2004] [Accepted: 08/11/2004] [Indexed: 11/22/2022]
Abstract
Nicotine has been shown in numerous previous studies to significantly improve memory on the radial-arm maze, yet the critical mechanisms underlying this effect are not fully characterized. Nicotine stimulates the release of a number of neurotransmitters important for memory function including (gamma-aminobutyric acid) GABA. The importance of nicotinic-GABA interactions regarding memory is currently unknown. The purpose of the current study was to determine the interactive effects of nicotine and the GABA agonist baclofen on working memory function as measured by choice accuracy in the radial-arm maze. Female Sprague-Dawley rats trained to asymptotic performance levels on a win-shift eight-arm radial maze task were used for assessment of nicotine-baclofen interactions. Low doses of baclofen improved memory performance while higher doses impaired it. Nicotine, as seen before, improved memory performance. Nicotine also significantly reversed the higher dose baclofen-induced deficit. These data show the importance of both nicotinic and GABA systems in working memory function and the interactions between these two transmitter receptor systems. This not only provides information concerning the neural bases of cognitive performance, it also lends insight into new combination treatments for memory impairment.
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Affiliation(s)
- Edward D Levin
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC 27710, USA.
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21
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Li S, Park MS, Kim MO. Prenatal alteration and distribution of the GABA(B1) and GABA(B2) receptor subunit mRNAs during rat central nervous system development. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2004; 150:141-50. [PMID: 15158077 DOI: 10.1016/j.devbrainres.2004.03.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/17/2004] [Indexed: 10/26/2022]
Abstract
The prenatal developmental expression changes and distribution of the gamma-aminobutyric acid (GABA)(B1) and GABA(B2) receptor subunit were investigated using in situ hybridization and RNase protection assay (RPA). We defined a different expression pattern of GABA(B1) subunit mRNA to that of GABA(B2) subunit. GABA(B1) subunit mRNA signals were moderately expressed in the cerebral cortex neuroepithelium of discrete brain regions on gestational day (GD) 11.5 and 12.5 and were highly expressed in the brain and spinal cord on GD 13.5 and 15.5. However, GABA(B2) subunit mRNAs were not detected on GD 11.5 and 12.5 and were first weakly detected on GD 13.5. On GD 15.5, 17.5, and 19.5, these subunit mRNAs were found in the retina, hippocampus, cerebral cortex, spinal cord, and cerebellum area. On GD 19.5 and 21.5, these subunits mRNA signals increased in the cerebral cortex, hippocampus, thalamus, and cerebellum, but decreased in the spinal cord, spinal ganglion, and midbrain, reaching similar levels to that of the adult brain. On GD 21.5, these subunit mRNAs were similarly expressed in almost all brain areas with a higher expression level of GABA(B1) subunit mRNA than GABA(B2) subunit mRNA. Our results found that GABA(B1) and GABA(B2) subunit mRNAs showed different expression patterns, with the GABA(B1) subunit expressed earlier and higher. We suggest that GABA(B1) and GABA(B2) subunits might have a role in the fetal brain during the gestational period for pre- and post-synaptogenesis, proliferation, differentiation, and neuronal maturation, and GABA(B1) subunit may be more important than GABA(B2) subunit during rat prenatal development.
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Affiliation(s)
- Shupeng Li
- Division of Life Science, College of Natural Sciences and Applied Life Science (Brain Korea 21), Gyeongsang National University, Chinju 660-701, South Korea
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22
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Amantea D, Tessari M, Bowery NG. Reduced G-protein coupling to the GABAB receptor in the nucleus accumbens and the medial prefrontal cortex of the rat after chronic treatment with nicotine. Neurosci Lett 2004; 355:161-4. [PMID: 14732456 DOI: 10.1016/j.neulet.2003.10.060] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The effect of repeated administration of nicotine (0.4 mg/kg, daily, s.c., for 14 days) on GABAB receptor density, affinity and G-protein coupling was investigated in the mesocorticolimbic system of the rat brain. Baclofen-stimulated [35S]GTPgammaS binding autoradiography revealed that the level of G-protein coupling to GABAB receptors was significantly reduced in the medial prefrontal cortex and the nucleus accumbens of nicotine-treated rats as compared to vehicle-injected controls. By contrast, GABAB receptor density and affinity, as revealed by [3H]GABA saturation binding autoradiography, were not altered by the nicotine exposure in any of the regions examined. Reduced G-protein coupling to the GABAB receptor may result in disinhibition of mesocorticolimbic dopaminergic neurones, which would contribute to the development of sensitised dopaminergic responses to repeated administration of nicotine.
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Affiliation(s)
- Diana Amantea
- Department of Pharmacology, Medical School, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
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23
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Kim MO, Li S, Park MS, Hornung JP. Early fetal expression of GABA(B1) and GABA(B2) receptor mRNAs on the development of the rat central nervous system. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2003; 143:47-55. [PMID: 12763580 DOI: 10.1016/s0165-3806(03)00099-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
GABA(B) receptors are G-protein-coupled receptors that mediate slow onset and prolonged effects of GABA in the central nervous system (CNS). While they appear to influence developmental events, depending on where they are found at a synapse, little, if anything, is known as to the expression of GABA(B1) and GABA(B2) receptor mRNAs during the early developmental stages. We used in situ hybridization and RNase protection assays (RPA) to investigate the early fetal expression of GABA(B1) and GABA(B2) receptor mRNAs on the development of the rat CNS. Our in situ studies defined a pattern of early and strong GABA(B1) receptor mRNA expression in the spinal cord, medullar and cerebral cortex neuroepithelium of discrete brain regions on gestational day (GD) 11.5. On GD 12.5, GABA(B1) receptor mRNAs were found in the hippocampal formation, cerebral cortex, intermediate and posterior neuroepithelium, and the pontine neuroepithelium of whole brain. RPA results showed GABA(B1) receptor mRNA was intensely expressed on GD 11.5 and GD 12.5, when it was first detected in the ganglia, thalamus, and cerebellum. However, GABA(B2) receptor mRNA was not detected on GD 10.5, 11.5, or 12.5. We suggest that GABA(B1) receptor might have a role in the early fetal brain and spinal cord during pre- and post-synaptogenesis, neuronal maturation, proliferation, and migration, and may be more important than the GABA(B2) receptor in the early development of the rat CNS.
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MESH Headings
- Animals
- Animals, Newborn
- Blotting, Northern/methods
- Central Nervous System/embryology
- Central Nervous System/metabolism
- Embryo, Mammalian
- Female
- Gene Expression Regulation, Developmental
- In Situ Hybridization/methods
- Male
- Pregnancy
- RNA Probes/chemistry
- RNA Probes/metabolism
- RNA, Messenger/biosynthesis
- Rats
- Rats, Sprague-Dawley
- Receptors, GABA/biosynthesis
- Receptors, GABA/genetics
- Receptors, GABA-B/biosynthesis
- Receptors, GABA-B/genetics
- Tissue Distribution
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Affiliation(s)
- Myeong Ok Kim
- Division of Life Science, College of Natural Sciences and Applied Life Science (BK21), Gyeongsang National University, Gazwa-dong 900, Chinju, 660-701, South Korea.
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