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Lee TA, Lee HJ, Mangieri RA, Gonzales R, Ajmal H, Hutter T. Time-course concentration of ethanol, acetaldehyde and acetate in rat brain dialysate following alcohol self-administration. Alcohol 2024:S0741-8329(24)00124-1. [PMID: 39243874 DOI: 10.1016/j.alcohol.2024.09.001] [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: 08/15/2024] [Revised: 09/02/2024] [Accepted: 09/04/2024] [Indexed: 09/09/2024]
Abstract
The unclear mechanisms of ethanol metabolism in the brain highlight the need for a deeper understanding of its metabolic pathways. This study used in vivo microdialysis to simultaneously sample ethanol and its metabolites, acetaldehyde and acetate, in the rat striatum following self-administration of ethanol, emphasizing the natural oral exposure route. To enhance the self-administration, rats underwent two-bottle-choice and limited access training. Dialysate samples, collected every 10 minutes for 2.5 hours, were analyzed using gas chromatography with flame ionization detection (GC-FID). The measured time courses of dialysate concentrations of ethanol, acetaldehyde, and acetate provided insights into dynamics of ethanol metabolism. Notably, in a subject with low ethanol consumption (0.29 g/kg), the concentration of acetaldehyde remained below the limit of detection throughout the experiment. However, the acetate concentration was clearly increased after ethanol consumption in this subject and was comparable to that of other rats with higher ethanol consumption. Compared with focusing only on peak values in the time-courses of concentrations of ethanol and its metabolites, calculating areas under curves provided better models of the relationships between ethanol intake and individual ethanol metabolites, as indicated by the r-square values for the linear regressions. This approach of using the area under the curve accounts for both the amplitude and duration of the concentration profiles, reducing the impact of variations in individual drinking patterns. In vivo microdialysis enables concurrent sampling of brain metabolites during oral ethanol administration, contributing insights into metabolite dynamics. To our knowledge, this paper is the first to report measurement of all three analytes in the brain following self-administration of ethanol. Future studies will explore regional variations and dynamics post-ethanol dependence, further advancing our understanding of ethanol metabolism in the brain.
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Affiliation(s)
- Tse-Ang Lee
- Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78712, USA
| | - Hongjoo J Lee
- Department of Psychology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Regina A Mangieri
- College of Pharmacy, Division of Pharmacology and Toxicology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Rueben Gonzales
- College of Pharmacy, Division of Pharmacology and Toxicology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Heba Ajmal
- Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, USA
| | - Tanya Hutter
- Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; Materials Science and Engineering Program and Texas Materials Institute, The University of Texas at Austin, Austin, TX 78712, USA.
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Carton L, Auger F, Laloux C, Durieux N, Kyheng M, Potey C, Bergeron S, Rolland B, Deguil J, Bordet R. Effects of acute ethanol and/or diazepam exposure on immediate and delayed hippocampal metabolite levels in rats anesthetized with isoflurane. Fundam Clin Pharmacol 2022; 36:687-698. [DOI: 10.1111/fcp.12764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 01/13/2022] [Accepted: 01/31/2022] [Indexed: 11/28/2022]
Affiliation(s)
- Louise Carton
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience and Cognition, Degenerative and Vascular Cognitive Disorders, UMR‐S1172, Pharmacology Department Lille France
| | - Florent Auger
- Lille In vivo Imaging and Functional Exploration platform Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, US 41‐UMS 2014‐PLBS Lille France
| | - Charlotte Laloux
- Lille In vivo Imaging and Functional Exploration platform Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, US 41‐UMS 2014‐PLBS Lille France
| | - Nicolas Durieux
- Lille In vivo Imaging and Functional Exploration platform Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, US 41‐UMS 2014‐PLBS Lille France
| | - Maéva Kyheng
- ULR 2694‐METRICS: Évaluation des Technologies de Santé et des Pratiques Médicales Univ. Lille, CHU Lille Lille France
- Département de Biostatistiques CHU Lille Lille France
| | - Camille Potey
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience and Cognition, Degenerative and Vascular Cognitive Disorders, UMR‐S1172, Pharmacology Department Lille France
| | - Sandrine Bergeron
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience and Cognition, Degenerative and Vascular Cognitive Disorders, UMR‐S1172, Pharmacology Department Lille France
| | - Benjamin Rolland
- Service Universitaire d'Addictologie de Lyon CH Le Vinatier, Hospices Civils de Lyon Bron France
- Inserm U1028, CNRS UMR5292 Université Claude Bernard Lyon 1 Bron France
| | - Julie Deguil
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience and Cognition, Degenerative and Vascular Cognitive Disorders, UMR‐S1172, Pharmacology Department Lille France
| | - Régis Bordet
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience and Cognition, Degenerative and Vascular Cognitive Disorders, UMR‐S1172, Pharmacology Department Lille France
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3
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Urbanik A, Kozub J, Karcz P, Ostrogórska M. Changes in the brain directly following alcohol consumption-a study of healthy male individuals, with the use of proton magnetic resonance spectroscopy (1HMRS) and diffusion (DWI). Alcohol Alcohol 2021; 56:415-424. [PMID: 33179046 DOI: 10.1093/alcalc/agaa119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 09/04/2020] [Accepted: 10/12/2020] [Indexed: 11/12/2022] Open
Abstract
AIMS To use proton magnetic resonance spectroscopy (1HMRS) and diffusion weighted imaging (DWI) to identify ethanol in the brain directly after consumption, and examine changes in brain metabolite levels and brain microstructure relative to the duration of time following exposure to alcohol. METHODS The study involved 44 male volunteers (18-55 years). All brain changes were assessed in the frontal lobes, occipital lobes, basal ganglia and cerebellum, however the detailed analyses focused on the frontal lobes. All participants were examined four times, i.e. before and 0.5-hour, 1 hour and 2 hours after consumption of 150 mL pure vodka (60 g of ethanol). RESULTS The highest ethanol levels were identified between 0.5 and 1 hour following alcohol intake. There were significant increases in the concentrations of lipids and lactates approximately one hour after alcohol consumption, and the concentration levels were found to normalise during the following two hours. Some statistically insignificant trends of changes were found for tCr, tCho, mI, GABA, Glc, Glx and tNAA. For the DWI and ADC (Apparent Diffusion Coefficient of water) values, the findings showed statistically insignificant decrease and increase, followed by a tendency towards normalisation. Similar associations in changes of metabolite concentrations and DWI and ADC values were found in the other locations investigated in the study. CONCLUSION A single dose of alcohol as used in this experiment produces increases in lipids and lactates in brain tissues that appear reversible.
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Affiliation(s)
- Andrzej Urbanik
- Department of Radiology, Collegium Medicum, Jagiellonian University, Krakow, Poland
| | - Justyna Kozub
- Department of Radiology, Collegium Medicum, Jagiellonian University, Krakow, Poland
| | - Paulina Karcz
- Department of Electroradiology, Collegium Medicum, Jagiellonian University, Krakow, Poland
| | - Monika Ostrogórska
- Department of Radiology, Collegium Medicum, Jagiellonian University, Krakow, Poland
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4
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Lovely CB. Quantification of Ethanol Levels in Zebrafish Embryos Using Head Space Gas Chromatography. J Vis Exp 2020. [PMID: 32116298 DOI: 10.3791/60766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Fetal Alcohol Spectrum Disorders (FASD) describe a highly variable continuum of ethanol-induced developmental defects, including facial dysmorphologies and neurological impairments. With a complex pathology, FASD affects approximately 1 in 100 children born in the United States each year. Due to the highly variable nature of FASD, animal models have proven critical in our current mechanistic understanding of ethanol-induced development defects. An increasing number of laboratories has focused on using zebrafish to examine ethanol-induced developmental defects. Zebrafish produce large numbers of externally fertilized, genetically tractable, translucent embryos. This allows researchers to precisely control timing and dosage of ethanol exposure in multiple genetic contexts and quantify the impact of embryonic ethanol exposure through live imaging techniques. This, combined with the high degree of conservation of both genetics and development with humans, has proven zebrafish to be a powerful model in which to study the mechanistic basis of ethanol teratogenicity. However, ethanol exposure regimens have varied between different zebrafish studies, which has confounded the interpretation of zebrafish data across these studies. Here is a protocol to quantify ethanol concentrations in zebrafish embryos using head space gas chromatography.
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Affiliation(s)
- C Ben Lovely
- Department of Biochemistry and Molecular Genetics, Alcohol Research Center, University of Louisville;
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Carton L, Auger F, Kyheng M, Pétrault M, Durieux N, Allorge D, Cottencin O, Jardri R, Bordet R, Rolland B. Dose-dependent metabolite changes after ethanol intoxication in rat prefrontal cortex using in vivo magnetic resonance spectroscopy. Sci Rep 2019; 9:10682. [PMID: 31337845 PMCID: PMC6650461 DOI: 10.1038/s41598-019-47187-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 07/10/2019] [Indexed: 11/09/2022] Open
Abstract
Ethanol disrupts the balance between the excitatory (glutamatergic) and inhibitory (GABAergic) neurotransmission systems. We aimed to assess how acute ethanol intoxication in rats affects the levels of GABA, glutamate and other cerebral metabolites after injection of two different doses of ethanol. One in vivo magnetic resonance spectrum of the prefrontal cortex region was acquired before and six spectra were acquired after intraperitoneal injections of saline or ethanol (1 g/kg or 2 g/kg). Brain kinetics after exposure to ethanol were compared to blood ethanol kinetics. GABA levels significantly decreased after injection of 1 g/kg but not 2 g/kg doses of ethanol. Choline levels, which serve as a marker of alterations in membrane composition, significantly decreased after injection of 2 g/kg but not 1 g/kg doses of ethanol. Acute ethanol intoxication appears to result in specific dose-dependent changes in the GABA level and choline level.
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Affiliation(s)
- Louise Carton
- University Lille, Inserm U1171 'Degenerative and vascular cognitive disorders', F-59000, Lille, France. .,CHU Lille, department of Pharmacology, F-59000, Lille, France. .,CHU Lille, Psychiatry and Addiction Medicine Department, F-59000, Lille, France.
| | - Florent Auger
- University Lille, Inserm U1171 'Degenerative and vascular cognitive disorders', F-59000, Lille, France.,University Lille, Preclinical Imaging Core Facility, F-59000 Lille, France
| | - Maeva Kyheng
- Univ. Lille, EA 2694 - Santé publique : épidémiologie et qualité des soins, F-59000 Lille, France.,CHU Lille, Service de Biostatistiques, F-59000 Lille, France
| | - Maud Pétrault
- University Lille, Inserm U1171 'Degenerative and vascular cognitive disorders', F-59000, Lille, France.,CHU Lille, department of Pharmacology, F-59000, Lille, France
| | - Nicolas Durieux
- University Lille, Preclinical Imaging Core Facility, F-59000 Lille, France
| | - Delphine Allorge
- CHU Lille, Unité Fonctionnelle de Toxicologie, F-59000, Lille, France.,University Lille, EA 4483 - IMPECS - IMPact de l'Environnement Chimique sur la Santé humaine, F-59000, Lille, France
| | - Olivier Cottencin
- CHU Lille, Psychiatry and Addiction Medicine Department, F-59000, Lille, France.,University Lille, CNRS UMR 9193 SCALab PsyCHIC Team, F-59000, Lille, France
| | - Renaud Jardri
- University Lille, CNRS UMR 9193 SCALab PsyCHIC Team, F-59000, Lille, France.,CHU Lille, Psychiatry Department, CURE platform, Fontan Hospital, F-59000, Lille, France
| | - Régis Bordet
- University Lille, Inserm U1171 'Degenerative and vascular cognitive disorders', F-59000, Lille, France.,CHU Lille, department of Pharmacology, F-59000, Lille, France
| | - Benjamin Rolland
- Service Universitaire d'Addictologie de Lyon (SUAL), Pôle MOPHA, CRNL, Inserm U1028, CNRS UMR5292, Université Lyon 1, Centre Hospitalier Le Vinatier, Bron, France
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6
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Broadwater MA, Lee SH, Yu Y, Zhu H, Crews FT, Robinson DL, Shih YYI. Adolescent alcohol exposure decreases frontostriatal resting-state functional connectivity in adulthood. Addict Biol 2018; 23:810-823. [PMID: 28691248 PMCID: PMC5760482 DOI: 10.1111/adb.12530] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 05/18/2017] [Accepted: 05/23/2017] [Indexed: 12/11/2022]
Abstract
Connectivity of the prefrontal cortex (PFC) matures through adolescence, coinciding with emergence of adult executive function and top-down inhibitory control over behavior. Alcohol exposure during this critical period of brain maturation may affect development of PFC and frontolimbic connectivity. Adult rats exposed to adolescent intermittent ethanol (AIE; 5 g/kg ethanol, 25 percent v/v in water, intragastrically, 2-day-on, 2-day-off, postnatal day 25-54) or water control underwent resting-state functional MRI to test the hypothesis that AIE induces persistent changes in frontolimbic functional connectivity under baseline and acute alcohol conditions (2 g/kg ethanol or saline, intraperitoneally administered during scanning). Data were acquired on a Bruker 9.4-T MR scanner with rats under dexmedetomidine sedation in combination with isoflurane. Frontolimbic network regions-of-interest for data analysis included PFC [prelimbic (PrL), infralimbic (IL), and orbitofrontal cortex (OFC) portions], nucleus accumbens (NAc), caudate putamen (CPu), dorsal hippocampus, ventral tegmental area, amygdala, and somatosensory forelimb used as a control region. AIE decreased baseline resting-state connectivity between PFC subregions (PrL-IL and IL-OFC) and between PFC-striatal regions (PrL-NAc, IL-CPu, IL-NAc, OFC-CPu, and OFC-NAc). Acute ethanol induced negative blood-oxygen-level-dependent changes within all regions of interest examined, along with significant increases in functional connectivity in control, but not AIE animals. Together, these data support the hypothesis that binge-like adolescent alcohol exposure causes persistent decreases in baseline frontolimbic (particularly frontostriatal) connectivity and alters sensitivity to acute ethanol-induced increases in functional connectivity in adulthood.
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Affiliation(s)
| | - Sung-Ho Lee
- Department of Neurology, University of North Carolina, Chapel Hill, NC, USA
- Departments of Biomedical Research Imaging Center and Biomedical Engineering, University of North Carolina, Chapel Hill, NC, USA
| | - Yang Yu
- Department of Statistics and Operations, University of North Carolina, Chapel Hill, NC, USA
- Departments of Biomedical Research Imaging Center and Biomedical Engineering, University of North Carolina, Chapel Hill, NC, USA
| | - Hongtu Zhu
- Department of Biostatistics, University of North Carolina, Chapel Hill, NC, USA
- Departments of Biomedical Research Imaging Center and Biomedical Engineering, University of North Carolina, Chapel Hill, NC, USA
| | - Fulton T. Crews
- Bowles Center for Alcohol Studies, University of North Carolina, Chapel Hill, NC, USA
- Department of Pharmacology, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Donita L. Robinson
- Bowles Center for Alcohol Studies, University of North Carolina, Chapel Hill, NC, USA
- Department of Psychiatry, University of North Carolina, Chapel Hill, NC, USA
| | - Yen-Yu Ian Shih
- Department of Neurology, University of North Carolina, Chapel Hill, NC, USA
- Departments of Biomedical Research Imaging Center and Biomedical Engineering, University of North Carolina, Chapel Hill, NC, USA
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7
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McDaid J, Abburi C, Wolfman SL, Gallagher K, McGehee DS. Ethanol-Induced Motor Impairment Mediated by Inhibition of α7 Nicotinic Receptors. J Neurosci 2016; 36:7768-78. [PMID: 27445152 PMCID: PMC4951579 DOI: 10.1523/jneurosci.0154-16.2016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 06/03/2016] [Accepted: 06/07/2016] [Indexed: 01/30/2023] Open
Abstract
UNLABELLED Nicotine and ethanol (EtOH) are among the most widely co-abused substances, and nicotinic acetylcholine receptors (nAChRs) contribute to the behavioral effects of both drugs. Along with their role in addiction, nAChRs also contribute to motor control circuitry. The α7 nAChR subtype is highly expressed in the laterodorsal tegmental nucleus (LDTg), a brainstem cholinergic center that contributes to motor performance through its projections to thalamic motor relay centers, including the mediodorsal thalamus. We demonstrate that EtOH concentrations just above the legal limits for intoxication in humans can inhibit α7 nAChRs in LDTg neurons from rats. This EtOH-induced inhibition is mediated by a decrease in cAMP/PKA signaling. The α7 nAChR-positive allosteric modulator PNU120596 [N-(5-chloro-2,4-dimethoxyphenyl)-N'-(5-methyl-3-isoxazolyl)-urea], which interferes with receptor desensitization, completely eliminated EtOH modulation of these receptors. These data suggest that EtOH inhibits α7 responses through a PKA-dependent enhancement of receptor desensitization. EtOH also inhibited the effects of nicotine at presynaptic α7 nAChRs on glutamate terminals in the mediodorsal thalamus. In vivo administration of PNU120596 either into the cerebral ventricles or directly into the mediodorsal thalamus attenuated EtOH-induced motor impairment. Thus, α7 nAChRs are likely important mediators of the motor impairing effects of moderate EtOH consumption. SIGNIFICANCE STATEMENT The motor-impairing effects of ethanol contribute to intoxication-related injury and death. Here we explore the cellular and neural circuit mechanisms underlying ethanol-induced motor impairment. Physiologically relevant concentrations of ethanol inhibit activity of a nicotinic receptor subtype that is expressed in brain areas associated with motor control. That receptor inhibition is mediated by decreased receptor phosphorylation, suggesting an indirect modulation of cell signaling pathways to achieve the physiological effects.
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Affiliation(s)
- John McDaid
- Department of Anesthesia and Critical Care and
| | | | - Shannon L Wolfman
- Committee on Neurobiology, University of Chicago, Chicago, Illinois 60637
| | | | - Daniel S McGehee
- Department of Anesthesia and Critical Care and Committee on Neurobiology, University of Chicago, Chicago, Illinois 60637
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8
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Shnitko TA, Spear LP, Robinson DL. Adolescent binge-like alcohol alters sensitivity to acute alcohol effects on dopamine release in the nucleus accumbens of adult rats. Psychopharmacology (Berl) 2016; 233:361-71. [PMID: 26487039 PMCID: PMC4840100 DOI: 10.1007/s00213-015-4106-8] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2015] [Accepted: 10/08/2015] [Indexed: 01/06/2023]
Abstract
UNLABELLED Rationale: Early onset of alcohol drinking has been associated with alcohol abuse in adulthood. The neurobiology of this phenomenon is unclear, but mesolimbic dopamine pathways, which are dynamic during adolescence, may play a role. OBJECTIVES We investigated the impact of adolescent binge-like alcohol on phasic dopaminergic neurotransmission during adulthood. METHODS Rats received intermittent intragastric ethanol, water, or nothing during adolescence. In adulthood, electrically evoked dopamine release and subsequent uptake were measured in the nucleus accumbens core at baseline and after acute challenge of ethanol or saline. RESULTS Adolescent ethanol exposure did not alter basal measures of evoked dopamine release or uptake. Ethanol challenge dose-dependently decreased the amplitude of evoked dopamine release in rats by 30–50 % in control groups, as previously reported, but did not alter evoked release in ethanol-exposed animals. To address the mechanism by which ethanol altered dopamine signaling, the evoked signals were modeled to estimate dopamine efflux per impulse and the velocity of the dopamine transporter. Dopamine uptake was slower in all exposure groups after ethanol challenge compared to saline, while dopamine efflux per pulse of electrical stimulation was reduced by ethanol only in ethanol-naive rats. CONCLUSIONS The results demonstrate that exposure to binge levels of ethanol during adolescence blunts the effect of ethanol challenge to reduce the amplitude of phasic dopamine release in adulthood. Large dopamine transients may result in more extracellular dopamine after alcohol challenge in adolescent-exposed rats and may be one mechanism by which alcohol is more reinforcing in people who initiated drinking at an early age.
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Affiliation(s)
- Tatiana A. Shnitko
- Bowles Center for Alcohol Studies, University of North Carolina, Chapel Hill, NC, USA
| | - Linda P. Spear
- Center for Development and Behavioral Neuroscience, Department of Psychology, Binghamton University, Binghamton, NY 13902, USA
| | - Donita L. Robinson
- Bowles Center for Alcohol Studies, University of North Carolina, Chapel Hill, NC, USA,Department of Psychiatry, University of North Carolina, Chapel Hill, NC, USA,Corresponding author: Donita L. Robinson, PhD, Bowles Center for Alcohol Studies, CB #7178, University of North Carolina, Chapel Hill, NC 27599–7178; ; Phone: 919–966–9178; Fax: 919–966–5679
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9
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Lovely CB, Eberhart JK. Commentary: catching a conserved mechanism of ethanol teratogenicity. Alcohol Clin Exp Res 2015; 38:2160-3. [PMID: 25156611 DOI: 10.1111/acer.12484] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 05/08/2014] [Indexed: 12/14/2022]
Abstract
BACKGROUND Due to its profound impact on human development, ethanol (EtOH) teratogenicity is a field of intense study. The complexity of variables that influence the outcomes of embryonic or prenatal EtOH exposure compels the use of animal models in which these variables can be isolated. METHODS Numerous model systems have been used in these studies. The zebrafish is a powerful model system, which has seen a recent increase in usage for EtOH studies. RESULTS Those using zebrafish for alcohol studies often face 2 questions: (i) How physiologically relevant are the doses of EtOH administered to zebrafish embryos? and (ii) Will the mechanisms of EtOH teratogenesis be conserved to other model systems and human? CONCLUSIONS The current article by Flentke and colleagues () helps to shed important light on these questions and clearly demonstrates that the zebrafish will be a valuable model system with which to understand EtOH teratogenicity.
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Affiliation(s)
- C Ben Lovely
- Department of Molecular Biosciences, Waggoner Center for Alcohol & Addiction Research, Institute for Cell and Molecular Biology, University of Texas at Austin, Austin, Texas
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10
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Abstract
Fetal Alcohol Spectrum Disorders (FASD) describes a wide range of phenotypic defects affecting facial and neurological development associated with ethanol teratogenicity. It affects approximately 1 in 100 children born in the United States each year. Genetic predisposition along with timing and dosage of ethanol exposure are critical in understanding the prevalence and variability of FASD. The zebrafish attributes of external fertilization, genetic tractability, and high fecundity make it a powerful tool for FASD studies. However, a lack of consensus of ethanol treatment paradigms has limited the interpretation of these various studies. Here we address this concern by examining ethanol tissue concentrations across timing and genetic background. We utilize headspace gas chromatography to determine ethanol concentration in the AB, fli1:EGFP, and Tu backgrounds. In addition, we treated these embryos with ethanol over two different developmental time windows, 6-24 h post fertilization (hpf) and 24-48 hpf. Our analysis demonstrates that embryos rapidly equilibrate to a sub-media level of ethanol. Embryos then maintain this level of ethanol for the duration of exposure. The ethanol tissue concentration level is independent of genetic background, but is timing-dependent. Embryos exposed from 6 to 24 hpf were 2.7-4.2-fold lower than media levels, while embryos were 5.7-6.2-fold lower at 48 hpf. This suggests that embryos strengthen one or more barriers to ethanol as they develop. In addition, both the embryo and, to a lesser extent, the chorion, surrounding the embryo are barriers to ethanol. Overall, this work will help tighten ethanol treatment regimens and strengthen zebrafish as a model of FASD.
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Affiliation(s)
- C Ben Lovely
- Molecular Biosciences, University of Texas at Austin, Austin, TX 78713, USA; Waggoner Center for Alcohol & Addiction Research, University of Texas at Austin, Austin, TX 78713, USA.
| | - Regina D Nobles
- Ophthalmology and Visual Science, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Johann K Eberhart
- Molecular Biosciences, University of Texas at Austin, Austin, TX 78713, USA; Waggoner Center for Alcohol & Addiction Research, University of Texas at Austin, Austin, TX 78713, USA
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11
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Common effects of fat, ethanol, and nicotine on enkephalin in discrete areas of the brain. Neuroscience 2014; 277:665-78. [PMID: 25086310 DOI: 10.1016/j.neuroscience.2014.07.050] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 07/09/2014] [Accepted: 07/14/2014] [Indexed: 01/27/2023]
Abstract
Fat, ethanol, and nicotine share a number of properties, including their ability to reinforce behavior and produce overconsumption. To test whether these substances act similarly on the same neuronal populations in specific brain areas mediating these behaviors, we administered the substances short-term, using the same methods and within the same experiment, and measured their effects, in areas of the hypothalamus (HYPO), amygdala (AMYG), and nucleus accumbens (NAc), on mRNA levels of the opioid peptide, enkephalin (ENK), using in situ hybridization and on c-Fos immunoreactivity (ir) to indicate neuronal activity, using immunofluorescence histochemistry. In addition, we examined for comparison another reinforcing substance, sucrose, and also took measurements of stress-related behaviors and circulating corticosterone (CORT) and triglycerides (TG), to determine if they contribute to these substances' behavioral and physiological effects. Adult Sprague-Dawley rats were gavaged three times daily over 5 days with 3.5 mL of water, Intralipid (20% v/v), ethanol (12% v/v), nicotine (0.01% w/v) or sucrose (22% w/v) (approximately 7 kcal/dose), and tail vein blood was collected for measurements of circulating CORT and TG. On day five, animals were sacrificed, brains removed, and the HYPO, AMYG, and NAc processed for single- or double-labeling of ENK mRNA and c-Fos-ir. Fat, ethanol, and nicotine, but not sucrose, increased the single- and double-labeling of ENK and c-Fos-ir in precisely the same brain areas, the middle parvocellular but not lateral area of the paraventricular nucleus, central but not basolateral nucleus of the AMYG, and core but not shell of the NAc. While having little effect on stress-related behaviors or CORT levels, fat, ethanol, and nicotine all increased circulating levels of TG. These findings suggest that the overconsumption of these three substances and their potential for abuse are mediated by the same populations of ENK-expressing neurons in specific nuclei of the hypothalamus and limbic system.
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12
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Liu H, Zheng W, Yan G, Liu B, Kong L, Ding Y, Shen Z, Tan H, Zhang G. Acute ethanol-induced changes in edema and metabolite concentrations in rat brain. BIOMED RESEARCH INTERNATIONAL 2014; 2014:351903. [PMID: 24783201 PMCID: PMC3982422 DOI: 10.1155/2014/351903] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 02/12/2014] [Accepted: 02/12/2014] [Indexed: 02/05/2023]
Abstract
The aim of this study is to describe the acute effects of EtOH on brain edema and cerebral metabolites, using diffusion weight imaging (DWI) and proton magnetic resonance spectroscopy ((1)H-MRS) at a 7.0T MR and to define changes in apparent diffusion coefficient (ADC) values and the concentration of metabolites in the rat brain after acute EtOH intoxication. ADC values in each ROI decreased significantly at 1 h and 3 h after ethanol administration. ADC values in frontal lobe were decreased significantly compared with other regions at 3 h. For EtOH/Cr+PCr and cerebral metabolites (Cho, Tau, and Glu) differing over time, no significant differences for Ins, NAA, and Cr were observed in frontal lobes. Regression analysis revealed a significant association between TSEtOH/Cr+PCr and TSCho, TSTau, TSGlu, and TSADC. The changes of ADC values in different brain regions reflect the process of the cytotoxic edema in vivo. The characterization of frontal lobes metabolites changes and the correlations between TSEtOH/Cr+PCr and TSCho, TSTau, and TSGlu provide a better understanding for the biological mechanisms in neurotoxic effects of EtOH on the brain. In addition, the correlations between TSEtOH/Cr+PCr and TSADC will help us to understand development of the ethanol-induced brain cytotoxic edema.
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Affiliation(s)
- Huimin Liu
- Department of Radiology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong 515041, China
- Department of Ultrasound, The Affiliated Yuebei People's Hospital of Shantou University Medical College, Shaoguan, Guangdong 512025, China
| | - Wenbin Zheng
- Department of Radiology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong 515041, China
- *Wenbin Zheng:
| | - Gen Yan
- Department of Radiology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong 515041, China
| | - Baoguo Liu
- Department of Neurosurgery, The Affiliated Yuebei People's Hospital of Shantou University Medical College, Shaoguan, Guangdong 512025, China
| | - Lingmei Kong
- Department of Radiology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong 515041, China
| | - Yan Ding
- Department of Radiology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong 515041, China
| | - Zhiwei Shen
- Department of Radiology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong 515041, China
| | - Hui Tan
- Department of Radiology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong 515041, China
| | - Guishan Zhang
- Department of Radiology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong 515041, China
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Magnetic resonance imaging biomarkers in patients with progressive ataxia: current status and future direction. THE CEREBELLUM 2013; 12:245-66. [PMID: 22828959 DOI: 10.1007/s12311-012-0405-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
A diagnostic challenge commonly encountered in neurology is that of an adult patient presenting with ataxia. The differential is vast and clinical assessment alone may not be sufficient due to considerable overlap between different causes of ataxia. Magnetic resonance (MR)-based biomarkers such as voxel-based morphometry, MR spectroscopy, diffusion-weighted and diffusion-tensor imaging and functional MR imaging are gaining great attention for their potential as indicators of disease. A number of studies have reported correlation with clinical severity and underlying pathophysiology, and in some cases, MR imaging has been shown to allow differentiation of conditions causing ataxia. However, despite recent advances, their sensitivity and specificity vary. In addition, questions remain over their validity and reproducibility, especially when applied in routine clinical practice. This article extensively reviews the current literature regarding MR-based biomarkers for the patient with predominantly adult-onset ataxia. Imaging features characteristic of a particular ataxia are provided and features differentiating ataxia groups and subgroups are discussed. Finally, discussion will turn to the feasibility of applying these biomarkers in routine clinical practice.
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Moschak TM, Mitchell SH. Sensitivity to reinforcer delay predicts ethanol's suppressant effects, but itself is unaffected by ethanol. Drug Alcohol Depend 2013; 132:22-8. [PMID: 23910798 PMCID: PMC3830544 DOI: 10.1016/j.drugalcdep.2013.07.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 07/05/2013] [Accepted: 07/05/2013] [Indexed: 11/30/2022]
Abstract
BACKGROUND Relative preference for smaller, sooner rewards over larger, later rewards ("delay discounting") is increased by acute ethanol. Additionally, drug-naïve levels of delay discounting can predict subsequent ethanol consumption. However, it is unknown whether these phenomena are driven by a difference in sensitivity to the reinforcer delay or a difference in sensitivity to the reinforcer magnitude, because typical delay discounting tasks manipulate both parameters simultaneously. METHODS To disambiguate these factors, two tasks were developed in which animals chose between levers with either different delay contingencies (adjusting delay task) or different magnitude contingencies (adjusting magnitude task). When task performance was stable, rats received ethanol (0, 0.6, and 0.9 g/kg, i.p.). RESULTS Ethanol did not affect sensitivity to delay or sensitivity to magnitude. However, responding was suppressed at the highest dose of ethanol (0.9 g/kg). Less suppression was found in animals exhibiting high levels of drug-naïve sensitivity to delay. CONCLUSION Thus, this study suggests that ethanol's effect on standard delay discounting tasks is not due to an alteration in sensitivity to delay or magnitude. Additionally, these data show that animals with high sensitivity to delay are resistant to the behaviorally suppressant effects of ethanol, which suggests that low tolerance for delayed rewards and low sensitivity to the behaviorally suppressant effects of ethanol may partly be driven by the same underlying mechanism.
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Affiliation(s)
- Travis M Moschak
- Oregon Health & Science University, Portland, OR 97239-3098, USA.
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Secchi O, Zinellu M, Spissu Y, Pirisinu M, Bazzu G, Migheli R, Desole MS, O′Neill RD, Serra PA, Rocchitta G. Further in-vitro characterization of an implantable biosensor for ethanol monitoring in the brain. SENSORS 2013; 13:9522-35. [PMID: 23881145 PMCID: PMC3758661 DOI: 10.3390/s130709522] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 07/04/2013] [Accepted: 07/17/2013] [Indexed: 12/31/2022]
Abstract
Ethyl alcohol may be considered one of the most widespread central nervous system (CNS) depressants in Western countries. Because of its toxicological and neurobiological implications, the detection of ethanol in brain extracellular fluid (ECF) is of great importance. In a previous study, we described the development and characterization of an implantable biosensor successfully used for the real-time detection of ethanol in the brain of freely-moving rats. The implanted biosensor, integrated in a low-cost telemetry system, was demonstrated to be a reliable device for the short-time monitoring of exogenous ethanol in brain ECF. In this paper we describe a further in-vitro characterization of the above-mentioned biosensor in terms of oxygen, pH and temperature dependence in order to complete its validation. With the aim of enhancing ethanol biosensor performance, different enzyme loadings were investigated in terms of apparent ethanol Michaelis-Menten kinetic parameters, viz. IMAX, KM and linear region slope, as well as ascorbic acid interference shielding. The responses of biosensors were studied over a period of 28 days. The overall findings of the present study confirm the original biosensor configuration to be the best of those investigated for in-vivo applications up to one week after implantation.
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Affiliation(s)
- Ottavio Secchi
- Department of Clinical and Experimental Medicine, Medical School, University of Sassari, Viale S. Pietro 43/b, Sassari 07100, Italy; E-Mails: (O.S.); (M.Z.); (Y.P.); (M.P.); (G.B.); (R.M.); (M.S.D.); (P.A.S.)
| | - Manuel Zinellu
- Department of Clinical and Experimental Medicine, Medical School, University of Sassari, Viale S. Pietro 43/b, Sassari 07100, Italy; E-Mails: (O.S.); (M.Z.); (Y.P.); (M.P.); (G.B.); (R.M.); (M.S.D.); (P.A.S.)
| | - Ylenia Spissu
- Department of Clinical and Experimental Medicine, Medical School, University of Sassari, Viale S. Pietro 43/b, Sassari 07100, Italy; E-Mails: (O.S.); (M.Z.); (Y.P.); (M.P.); (G.B.); (R.M.); (M.S.D.); (P.A.S.)
| | - Marco Pirisinu
- Department of Clinical and Experimental Medicine, Medical School, University of Sassari, Viale S. Pietro 43/b, Sassari 07100, Italy; E-Mails: (O.S.); (M.Z.); (Y.P.); (M.P.); (G.B.); (R.M.); (M.S.D.); (P.A.S.)
| | - Gianfranco Bazzu
- Department of Clinical and Experimental Medicine, Medical School, University of Sassari, Viale S. Pietro 43/b, Sassari 07100, Italy; E-Mails: (O.S.); (M.Z.); (Y.P.); (M.P.); (G.B.); (R.M.); (M.S.D.); (P.A.S.)
| | - Rossana Migheli
- Department of Clinical and Experimental Medicine, Medical School, University of Sassari, Viale S. Pietro 43/b, Sassari 07100, Italy; E-Mails: (O.S.); (M.Z.); (Y.P.); (M.P.); (G.B.); (R.M.); (M.S.D.); (P.A.S.)
| | - Maria Speranza Desole
- Department of Clinical and Experimental Medicine, Medical School, University of Sassari, Viale S. Pietro 43/b, Sassari 07100, Italy; E-Mails: (O.S.); (M.Z.); (Y.P.); (M.P.); (G.B.); (R.M.); (M.S.D.); (P.A.S.)
| | - Robert D. O′Neill
- UCD School of Chemistry and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland; E-Mail:
| | - Pier Andrea Serra
- Department of Clinical and Experimental Medicine, Medical School, University of Sassari, Viale S. Pietro 43/b, Sassari 07100, Italy; E-Mails: (O.S.); (M.Z.); (Y.P.); (M.P.); (G.B.); (R.M.); (M.S.D.); (P.A.S.)
| | - Gaia Rocchitta
- Department of Clinical and Experimental Medicine, Medical School, University of Sassari, Viale S. Pietro 43/b, Sassari 07100, Italy; E-Mails: (O.S.); (M.Z.); (Y.P.); (M.P.); (G.B.); (R.M.); (M.S.D.); (P.A.S.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +39-079-228-526; Fax: +39-079-228-525
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Kroenke CD, Flory GS, Park B, Shaw J, Rau AR, Grant KA. Chronic ethanol (EtOH) consumption differentially alters gray and white matter EtOH methyl ¹H magnetic resonance intensity in the primate brain. Alcohol Clin Exp Res 2013; 37:1325-32. [PMID: 23550738 DOI: 10.1111/acer.12097] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 12/22/2012] [Indexed: 11/30/2022]
Abstract
BACKGROUND In vivo magnetic resonance spectroscopy (MRS) has previously been used to directly monitor brain ethanol (EtOH). It has been proposed that the EtOH methyl ¹H resonance intensity is larger in EtOH-tolerant individuals than in sensitive individuals. To characterize the relationship between long-term EtOH exposure and the brain EtOH MRS intensity, we present data from a longitudinal experiment conducted using nonhuman primate subjects. METHODS In vivo MRS was used to measure the gray matter (GM) and white matter (WM) EtOH methyl ¹H MRS intensity in 18 adult male rhesus macaques at 4 time points throughout the course of a chronic drinking experiment. Time points were prior to EtOH drinking, following a 3-month EtOH induction procedure, and following 6, and 12 subsequent months of 22 h/d of "open access" to EtOH (4% w/v) and water. RESULTS The EtOH methyl ¹H MRS intensity, which we observed to be independent of age over the range examined, increased with chronic EtOH exposure in GM and WM. In GM, MRS intensity increased from naïve level following the EtOH induction period (90 g/kg cumulative EtOH intake). In WM, MRS intensity was not significantly different from the EtOH-naïve state until after 6 months of 22-hour free access (110 to 850 g/kg cumulative intake range). The WM MRS intensity in the EtOH-naïve state was positively correlated with future drinking, and the increase in WM MRS intensity was negatively correlated with the amount of EtOH consumed throughout the experiment. CONCLUSIONS Chronic exposure to EtOH is associated with brain changes that result in differential increases in EtOH MRS intensity in GM and WM. The EtOH-naïve WM MRS intensity pattern is consistent with its previously proposed relationship to innate tolerance to the intoxicating effects of EtOH. EtOH-dependent MRS intensity changes in GM required less EtOH exposure than was necessary to produce changes in WM. Within WM, an unexpected, potentially age dependent, enhanced sensitivity to EtOH in light drinkers relative to heavy drinkers was observed.
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Affiliation(s)
- Christopher D Kroenke
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Portland, OR 97239, USA.
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Marie N, Noble F. Dépendance aux drogues : avancées de la neurobiologie et perspectives thérapeutiques. Presse Med 2012; 41:1259-70. [DOI: 10.1016/j.lpm.2012.07.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Accepted: 07/31/2012] [Indexed: 02/08/2023] Open
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18
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Rocchitta G, Secchi O, Alvau MD, Migheli R, Calia G, Bazzu G, Farina D, Desole MS, O'Neill RD, Serra PA. Development and characterization of an implantable biosensor for telemetric monitoring of ethanol in the brain of freely moving rats. Anal Chem 2012; 84:7072-9. [PMID: 22823474 DOI: 10.1021/ac301253h] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ethanol is one of the most widespread psychotropic agents in western society. While its psychoactive effects are mainly associated with GABAergic and glutamatergic systems, the positive reinforcing properties of ethanol are related to activation of mesolimbic dopaminergic pathways resulting in a release of dopamine in the nucleus accumbens. Given these neurobiological implications, the detection of ethanol in brain extracellular fluid (ECF) is of great importance. In this study, we describe the development and characterization of an implantable biosensor for the amperometric detection of brain ethanol in real time. Ten different designs were characterized in vitro in terms of Michaelis-Menten kinetics (V(MAX) and K(M)), sensitivity (linear region slope, limit of detection (LOD), and limit of quantification (LOQ)), and electroactive interference blocking. The same parameters were monitored in selected designs up to 28 days after fabrication in order to quantify their stability. Finally, the best performing biosensor design was selected for implantation in the nucleus accumbens and coupled with a previously developed telemetric device for the real-time monitoring of ethanol in freely moving, untethered rats. Ethanol was then administered systemically to animals, either alone or in combination with ranitidine (an alcohol dehydrogenase inhibitor) while the biosensor signal was continuously recorded. The implanted biosensor, integrated in the low-cost telemetry system, was demonstrated to be a reliable device for the short-time monitoring of exogenous ethanol in brain ECF and represents a new generation of analytical tools for studying ethanol toxicokinetics and the effect of drugs on brain ethanol levels.
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Affiliation(s)
- Gaia Rocchitta
- Department of Clinical and Experimental Medicine, Medical School, University of Sassari, Viale S. Pietro 43/b, 07100 Sassari, Italy
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Gomez R, Behar KL, Watzl J, Weinzimer SA, Gulanski B, Sanacora G, Koretski J, Guidone E, Jiang L, Petrakis IL, Pittman B, Krystal JH, Mason GF. Intravenous ethanol infusion decreases human cortical γ-aminobutyric acid and N-acetylaspartate as measured with proton magnetic resonance spectroscopy at 4 tesla. Biol Psychiatry 2012; 71:239-46. [PMID: 21855054 PMCID: PMC3227760 DOI: 10.1016/j.biopsych.2011.06.026] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 06/21/2011] [Accepted: 06/22/2011] [Indexed: 11/17/2022]
Abstract
BACKGROUND Ethanol modulates glutamate and γ-aminobutyric (GABA) function. However, little is known about the acute pharmacologic effects of ethanol on levels of GABA, glutamate, and other metabolites measurable in the human cortex in vivo with proton magnetic resonance spectroscopy ((1)H-MRS). METHODS Eleven healthy social drinkers received two intravenous ethanol infusions that raised breath alcohol levels to a clamped plateau of 60 mg/dL over 60-70 min. The first infusion established tolerability of the procedure, and the second procedure, conducted 15 ± 12 days later, was performed during (1)H-MRS of occipital GABA, glutamate, and other metabolites. RESULTS The time course of brain ethanol approximated that of breath ethanol, but venous ethanol lagged by approximately 7 min. The GABA fell 13 ± 8% after 5 min of the ethanol infusion and remained reduced (p = .003) throughout the measurement. The combination of N-acetylaspartate and N-acetylaspartyl glutamate (summed as NAA) fell steadily during the infusion by 8 ± 3% (p = .0036). CONCLUSIONS Ethanol reduced cortical GABA and NAA levels in humans. Reductions in GABA levels are consistent with facilitation of GABA(A) receptor function by ethanol. The gradual decline in NAA levels suggests inhibition of neural or metabolic activity in the brain.
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Affiliation(s)
- Rosane Gomez
- Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
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Steiner MA, Lecourt H, Strasser DS, Brisbare-Roch C, Jenck F. Differential effects of the dual orexin receptor antagonist almorexant and the GABA(A)-α1 receptor modulator zolpidem, alone or combined with ethanol, on motor performance in the rat. Neuropsychopharmacology 2011; 36:848-56. [PMID: 21150905 PMCID: PMC3055732 DOI: 10.1038/npp.2010.224] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Current insomnia treatments such as γ-aminobutyric acid (GABA) receptor modulators are associated with sedative and muscle-relaxant effects, which increase when drug intake is combined with alcohol. This study compared the novel sleep-enabling compound almorexant (ACT-078573-hydrochloride), a dual orexin receptor antagonist, with the positive GABA(A)-α1 receptor modulator zolpidem. Both compounds were administered alone or in combination with ethanol, and their effects on forced motor performance were determined in Wistar rats upon waking after treatment. To detect substance-induced sedation and myorelaxation, time spent on an accelerating rotating rod (rotarod) and forepaw grip strength were measured. Zolpidem (10, 30, and 100 mg/kg, p.o.) and ethanol (0.32, 1, and 1.5 g/kg, i.p.) dose-dependently decreased rotarod performance and grip strength, whereas almorexant (30, 100, and 300 mg/kg, p.o.) did not. Doses of ethanol (0.32 and 1 g/kg), which were ineffective when administered alone, showed interactions with zolpidem (10 and 30 mg/kg) leading to reduced rotarod performance and grip strength; in contrast, combination of ethanol (0.32 and 1 g/kg) with almorexant (100 and 300 mg/kg) did not reduce performance or grip strength below ethanol alone. We conclude that unlike zolpidem, almorexant does not interfere with forced motor performance or grip strength in the rat, nor does it further increase the sedative effects of ethanol. Our results suggest that the effect of almorexant can be immediately reversed to full alertness like under physiological sleep, and that almorexant is less likely to show strong sedation, excessive myorelaxation, or interaction with alcohol than commonly prescribed hypnotics such as zolpidem.
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Affiliation(s)
- Michel A Steiner
- CNS-Pharmacology, Actelion Pharmaceuticals Ltd, Allschwil, Switzerland.
| | - Hugues Lecourt
- CNS-Pharmacology, Actelion Pharmaceuticals Ltd, Allschwil, Switzerland
| | - Daniel S Strasser
- CNS-Pharmacology, Actelion Pharmaceuticals Ltd, Allschwil, Switzerland
| | | | - François Jenck
- CNS-Pharmacology, Actelion Pharmaceuticals Ltd, Allschwil, Switzerland
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Yang S, Salmeron BJ, Ross TJ, Xi ZX, Stein EA, Yang Y. Lower glutamate levels in rostral anterior cingulate of chronic cocaine users - A (1)H-MRS study using TE-averaged PRESS at 3 T with an optimized quantification strategy. Psychiatry Res 2009; 174:171-6. [PMID: 19906515 PMCID: PMC2788034 DOI: 10.1016/j.pscychresns.2009.05.004] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2008] [Revised: 02/24/2009] [Accepted: 05/18/2009] [Indexed: 10/20/2022]
Abstract
Previous studies have shown significantly lower metabolism and functional activity in the anterior cingulate cortex (ACC) of human cocaine addicts. The present study examined whether this ACC hypoactivity is associated with altered glutamate (Glu), the primary excitatory neurotransmitter in the central nervous system (CNS), which has been recently implicated in drug addiction. Participants comprised 14 chronic cocaine addicts and 14 matched healthy volunteers who were examined using (1)H magnetic resonance spectroscopy at 3 T. A new quantification strategy for echo time (TE)-averaged point-resolved spectroscopy (PRESS) was applied to disentangle relaxation effects from J-evolution of coupled spin systems such as Glu. The concentrations of Glu as well as N-acetyl aspartate (NAA), total creatine (tCr), choline-containing compounds (tCho), and myo-inositol (Ins) were estimated from both groups. Glu/tCr was significantly lower in chronic cocaine users compared to control subjects and was significantly correlated with years of cocaine use. Glu/tCr was also positively correlated with NAA/tCr. NAA/tCr significantly decreased with age but was not significantly different between the two groups. These findings suggest a metabolic/neurotransmitter dysregulation associated with cocaine addiction and support a possible therapeutic intervention strategy aimed at normalizing the Glu transmission and function in the treatment of cocaine addiction.
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Affiliation(s)
- Shaolin Yang
- Neuroimaging Research Branch, National Institute on Drug Abuse (NIDA), National Institutes of Health (NIH), Baltimore, MD 21224, USA
| | - Betty Jo Salmeron
- Neuroimaging Research Branch, National Institute on Drug Abuse (NIDA), National Institutes of Health (NIH), Baltimore, MD 21224, USA
| | - Thomas J. Ross
- Neuroimaging Research Branch, National Institute on Drug Abuse (NIDA), National Institutes of Health (NIH), Baltimore, MD 21224, USA
| | - Zheng-Xiong Xi
- Chemical Biology Research Branch, National Institute on Drug Abuse (NIDA), National Institutes of Health (NIH), Baltimore, MD 21224, USA
| | - Elliot A. Stein
- Neuroimaging Research Branch, National Institute on Drug Abuse (NIDA), National Institutes of Health (NIH), Baltimore, MD 21224, USA
| | - Yihong Yang
- Neuroimaging Research Branch, National Institute on Drug Abuse (NIDA), National Institutes of Health (NIH), Baltimore, MD 21224, USA,Correspondence to: Yihong Yang, Ph.D., Neuroimaging Research Branch, National Institute on Drug Abuse, NIH, 251 Bayview Blvd, Suite 200, Room 07A709, Baltimore, MD 21224, Tel: 443-740-2648, Fax: 443-740-2816,
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The effect of ethanol on human brain metabolites longitudinally characterized by proton MR spectroscopy. J Cereb Blood Flow Metab 2009; 29:891-902. [PMID: 19240741 DOI: 10.1038/jcbfm.2009.12] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The effect ethanol exerts on the human brain has not yet been addressed by longitudinal magnetic resonance (MR) spectroscopic experiments. Therefore, we longitudinally characterized cerebral metabolite changes in 15 healthy individuals by proton magnetic resonance spectroscopy ((1)H-MRS) subsequent to the ingestion of a standard beverage (mean peak blood alcohol concentration (BAC): 51.43 +/- 10.27 mg/dL). Each participant was examined before, over 93.71 +/- 11.17 mins immediately after and 726.36 +/- 94.96 mins (12.11 +/ -1.58 h) past per os alcohol exposure. Fronto-mesial and cerebellar ethanol concentrations over time were similar as determined by the LCModel analysis of spectral data. Alcohol-induced changes of fronto-mesial creatine, choline, glucose, inositol and aspartate levels at 5.79 +/- 2.94 [corrected] mins upon ingestion as well as cerebellar choline and inositol levels at 8.64 +/- 2.98 [corrected] mins past exposure. Closely associated with ethanol concentrations, supratentorial creatine, choline, inositol and aspartate levels decreased after ethanol administration, whereas glucose levels increased. Similarly, infratentorial choline and inositol concentrations were negatively correlated with ethanol levels over time. There were no changes in N-acetyl-aspartate levels upon alcohol exposure. Furthermore, no influence of ethanol on brain water integrals was detected. Ethanol consumption may directly increase oxidative stress and the neuronal vulnerability to it. In addition, our results are compatible with ethanol-induced cell membrane modifications and alternative energy substrate usage upon alcohol exposure.
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Pfefferbaum A, Adalsteinsson E, Bell RL, Sullivan EV. Development and resolution of brain lesions caused by pyrithiamine- and dietary-induced thiamine deficiency and alcohol exposure in the alcohol-preferring rat: a longitudinal magnetic resonance imaging and spectroscopy study. Neuropsychopharmacology 2007; 32:1159-77. [PMID: 16723995 DOI: 10.1038/sj.npp.1301107] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Wernicke's encephalopathy (WE) is characterized by lesions in thalamus, hypothalamus (including mammillary nuclei), and inferior colliculi, results in serious disabilities, has an etiology of thiamine deficiency, is treatable with thiamine, and occurs most commonly with alcoholism. Despite decades of study, whether alcohol exposure exacerbates the neuropathology or retards its resolution remains controversial. To examine patterns of brain damage and recovery resulting from thiamine deprivation with and without alcohol exposure, we conducted in vivo magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) at 3 T in alcohol-preferring (P) rats, which had voluntarily consumed large amounts of alcohol before thiamine manipulation. A total of 18 adult male P rats (nine alcohol-exposed) received a thiamine-deficient diet for 2 weeks: 10 (five alcohol-exposed) received intraperitoneal (i.p.) pyrithiamine (PT) and eight (four alcohol-exposed) received i.p. thiamine supplementation. Neurological signs developed by day 14. Rats were scanned before thiamine depletion and 18 and 35 days after thiamine repletion. Two-dimensional J-resolved MRS single-voxel spectra with water reference were collected in a voxel subtending the thalamus; metabolite quantification was corrected for voxel tissue content. MRI identified significant enlargement of dorsal ventricles and increase in signal intensities in thalamus, inferior colliculi, and mammillary nuclei of PT compared with thiamine-treated (TT) groups from MRI 1-2, followed by significant normalization from MRI 2-3 in thalamus and colliculi, but not mammillary nuclei and lateral ventricles. Voxel-by-voxel analysis revealed additional hyperintense signal clusters in the dorsal and ventral hippocampus and enlargement of the fourth ventricle. MRS showed a significant decline and then partial recovery in thalamic N-acetylaspartate, a marker of neuronal integrity, in PT compared with TT rats, with no change detected in creatine, choline, or glutamate. PT rats with prior alcohol exposure exhibited attenuated recovery in the thalamus and arrested growth of the corpus callosum; further, two of the five alcohol-exposed PT rats died prematurely. Parenchymal and ventricular changes with thiamine manipulation concur with human radiological signs of WE. The enduring macrostructural and neurochemical abnormalities involving critical nodes of Papez circuit carry liabilities for development of amnesia and incomplete recovery from other cognitive and motor functions subserved by the affected neural systems.
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Mayer D, Zahr NM, Sullivan EV, Pfefferbaum A. In vivo metabolite differences between the basal ganglia and cerebellum of the rat brain detected with proton MRS at 3T. Psychiatry Res 2007; 154:267-73. [PMID: 17346948 PMCID: PMC1892789 DOI: 10.1016/j.pscychresns.2006.11.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2006] [Revised: 09/18/2006] [Accepted: 11/26/2006] [Indexed: 11/21/2022]
Abstract
In vivo magnetic resonance spectroscopy (MRS) enables non-invasive longitudinal tracking of brain chemistry changes that can accompany aging, neurodegenerative disease, drug addiction and experimental manipulations in animals modeling such conditions. J-coupled resonances, such as glutamate, which are highly relevant to neuropsychiatric conditions are difficult to resolve on a clinical 3T MR scanner using conventional one-dimensional MRS sequences. We, therefore, implemented Constant Time PRESS (CT-PRESS) to quantify major metabolite and neurotransmitter biochemical signals, including glutamate, in two brain regions of the rat, basal ganglia and cerebellum. We acquired spectra at two distinct time points in two independent groups of six rats and analyzed metabolite levels using either creatine or water as a reference. Our results provide evidence that CT-PRESS at 3T is adequate and reliable for in vivo detection and quantification of glutamate in the rat brain and that regional differences occur in the signal intensities of the major metabolites. That the directionality of the differences depends on whether creatine or water is used as a reference for metabolite levels emphasizes the benefit to in vivo MRS of incorporating methods to establish absolute baseline metabolite concentrations.
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Affiliation(s)
- Dirk Mayer
- Radiology Department Lucas MRS/I Center Stanford University, 1201 Welch Road, P-273, Stanford, California 94305-5488, USA.
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