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Comstock SM, Vaidya JG, Niciu MJ. Neurophysiological Correlates and Differential Drug Response in Subjects With a Family History of an Alcohol Use Disorder. CHRONIC STRESS (THOUSAND OAKS, CALIF.) 2019; 3:2470547019865267. [PMID: 31511840 PMCID: PMC6738944 DOI: 10.1177/2470547019865267] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 06/26/2019] [Indexed: 11/17/2022]
Abstract
A family history of an alcohol use disorder (AUD) has been shown to increase one's risk of developing an AUD. Additionally, a positive family history of AUD (family history positive (FHP)) has neurobiological and neuropsychopharmacological consequences, and this review summarizes differential drug response as well as neuroanatomical and neurocognitive correlates. FHP status is related to altered responses to a number of drugs, including substances with abuse liability like alcohol, opioids, amphetamines, and ketamine. FHP individuals demonstrate fewer aversive effects and more rewarding response to both alcohol and subanesthetic dose ketamine. Ketamine is a rapid-acting antidepressant, and several studies have reported that ketamine is more effective for FHP treatment-resistant depressed individuals. In short, the reviewed neurophysiological differences may contribute to ketamine's enhanced antidepressant efficacy in FHP patients. Volumetric differences in the amygdala, nucleus accumbens, neocortex, and cerebellum are commonly reported. Furthermore, FHP has also been associated with altered neurocognitive performance, e.g., increased impulsivity. The imaging and psychological literature supports a neurodevelopmental lag hypothesis in FHP youth. The review will further discuss these findings in depth.
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Affiliation(s)
- Sage M. Comstock
- Department of Psychiatry, Iowa
Neuroscience Institute, University of Iowa Health Care, Iowa City, IA, USA
| | - Jatin G. Vaidya
- Department of Psychiatry, Iowa
Neuroscience Institute, University of Iowa Health Care, Iowa City, IA, USA
| | - Mark J. Niciu
- Department of Psychiatry, Iowa
Neuroscience Institute, University of Iowa Health Care, Iowa City, IA, USA
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Wood EK, Kruger R, Bennion A, Cooke BM, Lindell S, Schwandt M, Goldman D, Barr CS, Suomi SJ, Higley JD. Low Inherent Sensitivity to the Intoxicating Effects of Ethanol in Rhesus Monkeys with Low CSF Concentrations of the Serotonin Metabolite 5-Hydroxyindoleacetic Acid. Alcohol Clin Exp Res 2018; 42:424-431. [PMID: 29125625 DOI: 10.1111/acer.13552] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 11/03/2017] [Indexed: 12/24/2022]
Abstract
BACKGROUND Type 2 alcoholism is characterized by low serotonin system functioning and has a high degree of heritability, with offspring of alcoholics often showing a reduced response to the intoxicating effects of ethanol (EtOH), which is thought to be marker for future alcohol use disorders (AUDs). As such, an important aim of studies investigating the origins of AUDs is to understand the relationship between serotonin system functioning and level of intoxication. A nonhuman primate model was used to evaluate observational ratings of sensitivity to EtOH and to further investigate the relationship between central serotonin activity and behavioral response to EtOH. METHODS Cerebrospinal fluid (CSF) concentrations of 5-hydroxyindoleacetic acid (5-HIAA) were obtained from 4 cohorts of alcohol-naïve, adolescent rhesus macaques (N = 82, 45 females, 37 males). One to 3 months after the CSF sample, subjects were administered a standardized intravenous EtOH bolus (males: 2.1 g/kg body weight, females: 2.0 g/kg body weight), placed into an open-top, clear plexiglass chamber suspended from the ceiling, and their latency to escape was recorded as a measure of the degree of intoxication. Thereafter, subjects were rated using a Likert scale for the degree of intoxication during a 30-minute observation period. RESULTS Our results indicate that latency to escape from the chamber was associated with intoxication ratings (p = 0.0009) following the standardized intravenous administration of EtOH. Low CSF 5-HIAA concentrations predicted short escape latency (p = 0.007) and were associated with low intoxication ratings (p = 0.02), indicating that low central nervous system (CNS) serotonin functioning is related to relative insensitivity to the intoxicating effects of alcohol. CONCLUSIONS Our study shows that, in monkeys exposed to alcohol for the first time, objective measures of intoxication are associated with subjective ratings for intoxication, and both were associated with CSF 5-HIAA concentrations. Our data confirm and extend the finding that low CNS serotonin functioning is predictive of intrinsic low sensitivity to the intoxicating effects of EtOH.
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Affiliation(s)
| | - Ryno Kruger
- Department of Psychology, Brigham Young University, Provo, Utah
| | - Angus Bennion
- Department of Psychology, Brigham Young University, Provo, Utah
| | | | - Stephen Lindell
- Laboratory of Clinical Studies, DICBR, NIAAA, Bethesda, Maryland
| | - Melanie Schwandt
- Laboratory of Clinical Studies, DICBR, NIAAA, Bethesda, Maryland
| | - David Goldman
- Laboratory of Neurogenetics, National Institute on Alcohol Abuse and Alcoholism, Rockville, Maryland
| | - Christina S Barr
- Laboratory of Clinical Studies, DICBR, NIAAA, Bethesda, Maryland
| | - Stephen J Suomi
- Laboratory of Comparative Ethology, NICHD, NIH Animal Center, Poolesville, Maryland
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Saalfield J, Spear L. The ontogeny of ethanol aversion. Physiol Behav 2016; 156:164-70. [PMID: 26774181 DOI: 10.1016/j.physbeh.2016.01.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 01/11/2016] [Accepted: 01/12/2016] [Indexed: 01/29/2023]
Abstract
Recent work has suggested separate developmental periods within the broader framework of adolescence, with data suggesting distinct alterations and vulnerabilities within these intervals. While previous research has suggested reduced sensitivity to the aversive effects of alcohol in adolescence relative to adults, a more detailed ontogeny of this effect has yet to be conducted. The adolescent brain undergoes significant transitions throughout adolescence, including in regions linked with drug reward and aversion. The current study aimed to determine the ontogeny of ethanol aversion by utilizing a conditioned taste aversion procedure at six different ages to test the hypothesis that the transitions into, through, and out of adolescence are associated with ontogenetic alterations in sensitivity to the aversive properties of ethanol. Non-deprived animals given Boost® as the conditioned stimulus (CS) were used in Experiment 1, whereas Experiment 2 used water-restricted animals provided with a saccharin/sucrose solution as the CS. In both experiments, an attenuated sensitivity to the aversive properties of ethanol was evident in adolescents compared to adults, although more age differences were apparent in water deprived animals than when a highly palatable CS was given to ad libitum animals. Overall, the data suggest an attenuated sensitivity to the aversive properties of ethanol that is most pronounced during pre- and early adolescence, declining thereafter to reach the enhanced aversive sensitivity of adults.
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Affiliation(s)
- Jessica Saalfield
- Binghamton University, PO Box 6000, Binghamton, NY 13902, United States.
| | - Linda Spear
- Binghamton University, PO Box 6000, Binghamton, NY 13902, United States
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Effect of sex on ethanol consumption and conditioned taste aversion in adolescent and adult rats. Psychopharmacology (Berl) 2014; 231:1831-9. [PMID: 24158502 PMCID: PMC4058910 DOI: 10.1007/s00213-013-3319-y] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 10/05/2013] [Indexed: 12/14/2022]
Abstract
RATIONALE Vulnerability to alcoholism is determined by many factors, including the balance of pleasurable vs. aversive alcohol-induced sensations: pleasurable sensations increase intake, while aversive sensations decrease it. Female sex and adolescent age are associated with lower sensitivity to intake-reducing effects and more rapid development of alcohol abuse. OBJECTIVES This study assessed voluntary drinking and the aversive effects of alcohol to determine whether these measures are inversely related across the sexes and development. METHODS Voluntary drinking of 20 % ethanol in an every-other-day (EOD) availability pattern and the dose-response relationship of ethanol conditioned taste aversion (CTA) were assessed in male and female adolescent and adult rats. RESULTS CTA was sex specific in adult but not adolescent rats, with adult females exhibiting less aversion. Voluntary ethanol consumption varied according to age and individual differences but was not sex specific. Adolescents initially drank more than adults, exhibited greater day-to-day variation in consumption, were more susceptible to the alcohol deprivation effect, and took longer to establish individual differences in consumption patterns. CONCLUSIONS These results show that the emergence of intake patterns differs between adolescents and adults. Adolescents as a group initiate drinking at high levels but decrease intake as they mature. A subset of adolescents maintained high drinking levels into adulthood. In contrast, most adults consumed at steady, low levels, but a small subset quickly established and maintained high-consumption patterns. Adolescents also showed marked deprivation-induced increases. Sex differences were not observed in EOD drinking during either adolescence or adulthood.
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Matsushita S, Higuchi S. Genetic differences in response to alcohol. HANDBOOK OF CLINICAL NEUROLOGY 2014; 125:617-27. [PMID: 25307600 DOI: 10.1016/b978-0-444-62619-6.00036-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The level of response to alcohol, which reflects individual differences in sensitivity to the pharmacologic effects of alcohol, is considered to be an important endophenotype of alcohol use disorder (AUD). By comparing monozygotic and dizygotic twins, the heritability of the level of response to alcohol has been estimated to be 60%. Many genes have been implicated as potential contributors toward heavy drinking, alcohol-related problems, and AUD through a low level of response to alcohol, each with a small effect. Identified are genes for gamma-aminobutyric acid (GABA) receptors, serotonin transporter, opioid receptor, and nicotinic acetylcholine receptor, but the most well-characterized genes that have a strong impact on the level of response to alcohol are those for alcohol-metabolizing enzymes. Although two genetic variations in alcohol and aldehyde dehydrogenases, which have been the most intensively studied, exist almost exclusively in Asian populations, studies on the effect of genetic variations in alcohol-metabolizing enzymes on the response to alcohol are gradually expanding in non-Asian populations. In this chapter, we focus on genetic studies in humans. After analyzing the overall influence of genetic factors on the response to alcohol, we explore individual genes that may influence the response to alcohol. Lastly, we review studies examining the effects of genetic variations in alcohol-metabolizing enzymes on the level of response to alcohol.
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Affiliation(s)
- Sachio Matsushita
- National Hospital Organization, Kurihama Medical and Addiction Center, Kanagawa, Japan.
| | - Susumu Higuchi
- National Hospital Organization, Kurihama Medical and Addiction Center, Kanagawa, Japan
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Setiawan E, Pihl RO, Dagher A, Schlagintweit H, Casey KF, Benkelfat C, Leyton M. Differential Striatal Dopamine Responses Following Oral Alcohol in Individuals at Varying Risk for Dependence. Alcohol Clin Exp Res 2013; 38:126-34. [DOI: 10.1111/acer.12218] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 05/15/2013] [Indexed: 11/26/2022]
Affiliation(s)
- Elaine Setiawan
- Department of Psychiatry; McGill University; Montréal Québec Canada
- Department of Neurology and Neurosurgery; McGill University; Montréal Québec Canada
| | - Robert O. Pihl
- Department of Psychiatry; McGill University; Montréal Québec Canada
- Department of Psychology; McGill University; Montréal Québec Canada
| | - Alain Dagher
- Department of Neurology and Neurosurgery; McGill University; Montréal Québec Canada
| | | | - Kevin F. Casey
- Department of Psychiatry; McGill University; Montréal Québec Canada
- Department of Neurology and Neurosurgery; McGill University; Montréal Québec Canada
| | - Chawki Benkelfat
- Department of Psychiatry; McGill University; Montréal Québec Canada
- Department of Neurology and Neurosurgery; McGill University; Montréal Québec Canada
| | - Marco Leyton
- Department of Psychiatry; McGill University; Montréal Québec Canada
- Department of Neurology and Neurosurgery; McGill University; Montréal Québec Canada
- Department of Psychology; McGill University; Montréal Québec Canada
- Center for Studies in Behavioral Neurobiology; Concordia University; Montréal Québec Canada
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Santos N, Chatterjee S, Henry A, Holgate J, Bartlett SE. The α5 neuronal nicotinic acetylcholine receptor subunit plays an important role in the sedative effects of ethanol but does not modulate consumption in mice. Alcohol Clin Exp Res 2012; 37:655-62. [PMID: 23164049 DOI: 10.1111/acer.12009] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Accepted: 08/15/2012] [Indexed: 11/29/2022]
Abstract
BACKGROUND Alcohol use disorders (AUDs) are a major public health problem, and the few treatment options available to those seeking treatment offer only modest success rates. There remains a need to identify novel targets for the treatment of AUDs. The neuronal nicotinic acetylcholine receptors (nAChRs) represent a potential therapeutic target in the brain, as recent human genetic studies have implicated gene variants in the α5 nAChR subunit as high risk factors for developing alcohol dependence. METHODS Here, we evaluate the role of the α5* nAChR for ethanol (EtOH)-mediated behaviors using male α5+/+ and α5-/- transgenic mice. We characterized the effect of hypnotic doses of EtOH and investigated drinking behavior using an adapted drinking-in-the-dark (DID) paradigm that has been shown to induce high EtOH consumption in mice. RESULTS We found the α5 subunit to be important in mediating the sedative effects of EtOH. The α5-/- mice showed slower recovery from EtOH-induced sleep, as measured by loss of righting reflex. Additionally, the α5-/- mice showed enhanced impairment to EtOH-induced ataxia. We found the initial sensitivity to EtOH and EtOH metabolism to be similar in both α5+/+ and α5-/- mice. Hence, the enhanced sedation is likely due to a difference in the acute tolerance of EtOH in α5-/- mice. However, the α5 subunit did not play a role in EtOH consumption for EtOH concentrations ranging from 5 to 30% using the DID paradigm. Additionally, varenicline was effective in reducing EtOH intake in α5-/- mice. CONCLUSIONS Together, our data suggest that the α5 nAChR subunit is important for the sedative effects of EtOH but does not play a role in EtOH consumption in male mice. Varenicline can be a treatment option even when there is loss of function of the α5 nAChR subunit.
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Affiliation(s)
- Nathan Santos
- Ernest Gallo Clinic and Research Center, University of California-San Francisco, Emeryville, CA, USA
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Melón LC, Boehm SL. Role of genotype in the development of locomotor sensitization to alcohol in adult and adolescent mice: comparison of the DBA/2J and C57BL/6J inbred mouse strains. Alcohol Clin Exp Res 2011; 35:1351-60. [PMID: 21410489 DOI: 10.1111/j.1530-0277.2011.01471.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Animal models that explore differential sensitivity to the effects of acute and repeated exposure of alcohol (ethanol) may be influenced by both the developmental and genetic profile of the population. Therefore, we sought to compare the influence of ontogeny on sensitivity to ethanol-induced locomotor stimulation and on the induction of locomotor sensitization to this effect across 2 inbred strains of mice; the ethanol consuming C57BL/6J and the ethanol avoiding DBA/2J strains. METHODS C57BL/6J and DBA/2J adults (postnatal day [PD] 60 to 80) and adolescents (PD 30±2) were assessed for basal activity, acute response to 2.0 g/kg ethanol, and the expression of locomotor sensitization following repeated administration of 2.5, 3.0, or 3.5 g/kg ethanol. RESULTS Basal activity was different across development for the C57BL/6J, but not DBA/2J, with adult B6 mice showing persistently greater baseline activity. Adolescents of both strains were more sensitive than adults to acute ethanol-induced locomotor stimulation; adults exhibited a decrease in their acute response across the testing session. Adolescent DBA/2J mice developed less ethanol sensitization compared to adults, with significant sensitization observed only following repeated administration of the lowest ethanol dose (2.5 g/kg), whereas DBA/2J adults sensitized to all doses. Age did not influence the development of ethanol sensitization for the C57BL/6J strain, as both adults and adolescents displayed a sensitized response following all ethanol doses. CONCLUSIONS These results suggest that the developmental pattern of locomotor sensitivity to ethanol is unique to the genotypic profile of the animal model.
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Affiliation(s)
- Laverne C Melón
- Center for Developmental and Behavioral Neuroscience, Department of Psychology, Binghamton University, Binghamton, NY, USA.
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Evans SM, Levin FR. Response to alcohol in women: role of the menstrual cycle and a family history of alcoholism. Drug Alcohol Depend 2011; 114:18-30. [PMID: 20888148 PMCID: PMC3017640 DOI: 10.1016/j.drugalcdep.2010.09.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Revised: 08/27/2010] [Accepted: 09/01/2010] [Indexed: 10/19/2022]
Abstract
The present study determined whether: (1) the response to alcohol varied as a function of menstrual cycle phase and (2) women with a paternal history of alcoholism (FHP) were less sensitive to the effects of alcohol compared to women without a family history of alcoholism (FHN). The behavioral effects of alcohol (0.00, 0.25, and 0.75 g/kg) were evaluated in 21 FHN and 24 FHP women; each dose was tested during both the midfollicular and late luteal phases of the menstrual cycle. Baseline negative mood was increased during the luteal phase compared to the follicular phase (increased Beck Depression scores and decreased Vigor, Arousal, and Friendly scores). Alcohol increased ratings of Drug Liking and Good Drug Effect more in the luteal phase than the follicular phase. FHP women had greater negative mood during the luteal phase and some of these dysphoric effects were increased by alcohol more in FHP women than FHN women. Alcohol impaired performance, with no group or menstrual cycle differences. However, consistent with previous studies, FHP women were less impaired by alcohol than FHN women on the balance task. These data indicate that (1) the differences in response to alcohol across the menstrual cycle are subtle, although alcohol is liked more during the luteal phase; (2) increases in dysphoric mood during the luteal phase are more pronounced in FHP women compared to FHN women, particularly after alcohol; and (3) the differences observed in response to alcohol between FHP and FHN women are less pronounced than previously shown in men.
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Affiliation(s)
- Suzette M Evans
- New York State Psychiatric Institute and Departmentof Psychiatry, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA.
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Schramm-Sapyta NL, DiFeliceantonio AG, Foscue E, Glowacz S, Haseeb N, Wang N, Zhou C, Kuhn CM. Aversive effects of ethanol in adolescent versus adult rats: potential causes and implication for future drinking. Alcohol Clin Exp Res 2010; 34:2061-9. [PMID: 20860614 DOI: 10.1111/j.1530-0277.2010.01302.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
BACKGROUND Many people experiment with alcohol and other drugs of abuse during their teenage years. Epidemiological evidence suggests that younger initiates into drug taking are more likely to develop problematic drug seeking behavior, including binge and other high-intake behaviors. The level of drug intake for any individual depends on the balance of rewarding and aversive effects of the drug in that individual. Multiple rodent studies have demonstrated that aversive effects of drugs of abuse are reduced in adolescent compared to adult animals. In this study, we addressed 2 key questions: First, do reduced aversive effects of ethanol in younger rats correlate with increased ethanol consumption? Second, are the reduced aversive effects in adolescents attributable to reduced sensitivity to ethanol's physiologic effects? METHODS Adolescent and adult rats were tested for ethanol conditioned taste aversion (CTA) followed by a voluntary drinking period, including postdeprivation consumption. Multivariate regression was used to assess correlations. In separate experiments, adolescent and adult rats were tested for their sensitivity to the hypothermic and sedative effects of ethanol, and for blood ethanol concentrations (BECs). RESULTS We observed that in adolescent rats but not adults, taste aversion was inversely correlated with postdeprivation consumption. Adolescents also exhibited a greater increase in consumption after deprivation than adults. Furthermore, the age difference in ethanol CTA was not attributable to differences in hypothermia, sedation, or BECs. CONCLUSIONS These results suggest that during adolescence, individuals that are insensitive to aversive effects are most likely to develop problem drinking behaviors. These results underscore the importance of the interaction between developmental stage and individual variation in sensitivity to alcohol.
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Crabbe JC, Bell RL, Ehlers CL. Human and laboratory rodent low response to alcohol: is better consilience possible? Addict Biol 2010; 15:125-44. [PMID: 20148776 DOI: 10.1111/j.1369-1600.2009.00191.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
If people are brought into the laboratory and given alcohol, there are pronounced differences among individuals in many responses to the drug. Some participants in alcohol challenge protocols show a cluster of 'low level of responses to alcohol' determined by observing post-drinking-related changes in subjective, motor and physiological effects at a given dose level. Those individuals characterized as having low level of response (LR) to alcohol have been shown to be at increased risk for a lifetime diagnosis of alcohol dependence (AD), and this relationship between low LR and AD appears to be in part genetic. LR to alcohol is an area where achieving greater consilience between the human and the rodent phenotypes would seem to be highly likely. However, despite extensive data from both human and rodent studies, few attempts have been made to evaluate the human and animal data systematically in order to understand which aspects of LR appear to be most directly comparable across species and thus the most promising for further study. We review four general aspects of LR that could be compared between humans and laboratory animals: (1) behavioral measures of subjective intoxication; (2) body sway; (3) endocrine responses; and (4) stimulant, autonomic and electrophysiological responses. None of these aspects of LR provide completely face-valid direct comparisons across species. Nevertheless, one of the most replicated findings in humans is the low subjective response, but, as it may reflect either aversively valenced and/or positively valenced responses to alcohol as usually assessed, it is unclear which rodent responses are analogous. Stimulated heart rate appears to be consistent in animal and human studies, although at-risk subjects appear to be more rather than less sensitive to alcohol using this measure. The hormone and electrophysiological data offer strong possibilities of understanding the neurobiological mechanisms, but the rodent data in particular are rather sparse and unsystematic. Therefore, we suggest that more effort is still needed to collect data using refined measures designed to be more directly comparable in humans and animals. Additionally, the genetically mediated mechanisms underlying this endophenotype need to be characterized further across species.
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Affiliation(s)
- John C Crabbe
- Portland Alcohol Research Center, Department of Behavioral Neuroscience, Oregon Health & Science University and VA Medical Center, Portland, OR 97239, USA.
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Rezvani AH, Sexton H, Levin ED. Persistent high alcohol consumption in alcohol-preferring (P) rats results from a lack of normal aversion to alcohol. Alcohol Alcohol 2010; 45:219-22. [PMID: 20356869 DOI: 10.1093/alcalc/agq020] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
AIMS In this study, we tested the impact of pretreatment with alcohol on subsequent alcohol drinking in outbred Sprague-Dawley and selectively bred alcohol-preferring (P) rats. METHODS As a pretreatment, male Sprague-Dawley and P rats were given a passive oral administration of either alcohol (1.0 g/kg) or tap water. Then, they were given free choice of drinking alcohol (5% v/v) or water in their home cages, which was measured over 4 weeks. RESULTS Without alcohol pretreatment, there was no significant strain difference in alcohol preference; both strains preferred 5% (v/v) alcohol solution. The strain difference was only apparent in the groups given alcohol pretreatment. This arose from the fact that alcohol pretreatment significantly reduced alcohol preference in the Sprague-Dawley rats to a level well below 50%, while it did not alter drinking behavior in P rats. The same effects were seen with total alcohol consumption (g/kg/day). These effects persisted throughout the 4 weeks of the study. CONCLUSIONS The principal difference between the Sprague-Dawley and P rats was that the P rats did not show the normal aversion to alcohol after forced exposure to alcohol that the Sprague-Dawley rats showed. One of the potential contributors to high alcohol intake and preference in P rats may be lack of sensitivity to aversive effects of alcohol.
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Affiliation(s)
- Amir H Rezvani
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Box 3412, Durham, NC 27710, USA.
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Scherrer JF, Grant JD, Duncan AE, Sartor CE, Haber JR, Jacob T, Bucholz KK. Subjective effects to cannabis are associated with use, abuse and dependence after adjusting for genetic and environmental influences. Drug Alcohol Depend 2009; 105:76-82. [PMID: 19628344 PMCID: PMC3633518 DOI: 10.1016/j.drugalcdep.2009.06.014] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2008] [Revised: 04/24/2009] [Accepted: 06/12/2009] [Indexed: 10/20/2022]
Abstract
BACKGROUND Previous reports in adults have suggested that the effects experienced after cannabis use can be described in terms of positive and negative subtypes that are heritable and are associated with abuse and dependence. This study extends existing research by inclusion of adolescents and young adults in an offspring of twins design which makes it possible to take into account genetic and environmental risks for substance use disorder. METHODS Data were collected from 725 twin members of the Vietnam Era Twin Registry, 839 of their 12-32 year old biological offspring and 427 mothers. Offspring who had ever used cannabis (n=464) were asked the degree to which they typically experienced 13 subjective effects shortly after using cannabis. Latent class analysis (LCA) was used to derive subjective effect classes and logistic regression models were computed to test associations between subjective effect class and heavy cannabis use, abuse and dependence after adjusting for familial risk and psychopathology and sociodemographics. RESULTS The best fitting LCA model included 4 classes of responders which were characterized as 'high responders' (39%), 'positive responders' (28%), 'mixed/relaxed' (22%), and 'low responders' (11%). Compared to low responders, members of other classes were heavier users (OR range 3.0-11.8). Compared to mixed/relaxed responders and positive responders, high responders were more likely to have cannabis abuse and dependence. CONCLUSIONS Subjective reactions to cannabis use are associated with use to heavy use, abuse and dependence in adolescents and young adults. This association exists above and beyond the genetic vulnerability for problem cannabis use.
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Affiliation(s)
- Jeffrey F. Scherrer
- Research Service, St. Louis Veterans Affairs Medical Center, Research Service (151-JC), 915 North Grand Blvd, St. Louis, MO, United States,Midwest Alcoholism Research Center, Department of Psychiatry, Washington University School of Medicine, 660 S. Euclid Avenue, Campus Box 8134, St. Louis, MO 63110, United States,Corresponding author at: Washington University School of Medicine, 660 South Euclid Ave, Campus Box 8134, St. Louis, MO 63110, United States. Tel.: +1 314 286 2226; fax: +1 314 286 2213. (J.F. Scherrer)
| | - Julia D. Grant
- Midwest Alcoholism Research Center, Department of Psychiatry, Washington University School of Medicine, 660 S. Euclid Avenue, Campus Box 8134, St. Louis, MO 63110, United States
| | - Alexis E. Duncan
- Midwest Alcoholism Research Center, Department of Psychiatry, Washington University School of Medicine, 660 S. Euclid Avenue, Campus Box 8134, St. Louis, MO 63110, United States
| | - Carolyn E. Sartor
- Midwest Alcoholism Research Center, Department of Psychiatry, Washington University School of Medicine, 660 S. Euclid Avenue, Campus Box 8134, St. Louis, MO 63110, United States
| | - Jon R. Haber
- Midwest Alcoholism Research Center, Department of Psychiatry, Washington University School of Medicine, 660 S. Euclid Avenue, Campus Box 8134, St. Louis, MO 63110, United States,Palo Alto Department of Veterans Affairs Medical Center, MC 151J, 795 Willow Road, Palo Alto, CA 94025, United States
| | - Theodore Jacob
- Midwest Alcoholism Research Center, Department of Psychiatry, Washington University School of Medicine, 660 S. Euclid Avenue, Campus Box 8134, St. Louis, MO 63110, United States,Palo Alto Department of Veterans Affairs Medical Center, MC 151J, 795 Willow Road, Palo Alto, CA 94025, United States
| | - Kathleen K. Bucholz
- Research Service, St. Louis Veterans Affairs Medical Center, Research Service (151-JC), 915 North Grand Blvd, St. Louis, MO, United States,Midwest Alcoholism Research Center, Department of Psychiatry, Washington University School of Medicine, 660 S. Euclid Avenue, Campus Box 8134, St. Louis, MO 63110, United States
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Trim RS, Schuckit MA, Smith TL. The relationships of the level of response to alcohol and additional characteristics to alcohol use disorders across adulthood: a discrete-time survival analysis. Alcohol Clin Exp Res 2009; 33:1562-70. [PMID: 19485971 DOI: 10.1111/j.1530-0277.2009.00984.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND A low level of response (LR) to alcohol has been shown to relate to a higher risk for alcohol use disorders (AUDs). However, no previous research has examined the association between LR and the development of AUDs in the context of additional robust risk factors for AUDs. This study evaluated whether LR and other related characteristics predicted the occurrence of AUDs across adulthood using discrete-time survival analysis (DTSA). METHODS A total of 297 probands from the San Diego Prospective Study reported on the LR to alcohol, a family history (FH) of AUDs, the typical drinking quantity, the age of drinking onset, the body mass index and the age at the baseline (T1) assessment. Alcohol use disorders (AUDs) were evaluated at the 10-year (T10), T15, T20, and T25 follow-ups. RESULTS A low LR to alcohol predicted AUD occurrence over the course of adulthood even after controlling for the effects of other robust risk factors. Interaction effects revealed that the impact of FH on AUDs was only observed for subjects with high T1 drinking levels, and probands with high T1 drinking were at high risk for AUDs regardless of their age of onset. CONCLUSIONS The findings illustrate that LR is a unique risk factor for AUDs across adulthood, and not simply a reflection of a broader range of risk factors. The continued investigation of how LR is related to AUD onset later in life will help inform treatment providers about this high-risk population, and future longitudinal evaluations will utilize DTSA to assess rates of AUD remission as well as the onset of drinking outcomes in adolescent samples.
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Affiliation(s)
- Ryan S Trim
- Department of Psychiatry, University of California, San Diego, CA 92161-2002, USA.
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15
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Mandt BH, Schenk S, Zahniser NR, Allen RM. Individual differences in cocaine-induced locomotor activity in male Sprague-Dawley rats and their acquisition of and motivation to self-administer cocaine. Psychopharmacology (Berl) 2008; 201:195-202. [PMID: 18685831 PMCID: PMC2772105 DOI: 10.1007/s00213-008-1265-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Accepted: 07/17/2008] [Indexed: 11/29/2022]
Abstract
RATIONALE Factors that increase an individual's susceptibility to cocaine dependence remain largely unknown. We have previously shown that adult outbred male Sprague-Dawley rats can be classified as either low or high cocaine responders (LCRs or HCRs, respectively) based on their locomotor activity following the administration of a single dose of cocaine (10 mg/kg, i.p.). Furthermore, LCR/HCR classification predicts dopamine transporter function/inhibition, cocaine-induced locomotor sensitization, and cocaine-conditioned place preference. OBJECTIVES The present study assessed LCR/HCR classification and the development of locomotor sensitization on the latency to acquire cocaine self-administration and motivation to self-administer cocaine. RESULTS LCRs and HCRs did not differ in their latency to acquire low-dose cocaine self-administration (0.25 mg/kg/infusion over 12 s, fixed ratio 1 schedule of reinforcement). In a follow-up experiment, repeated experimenter-administered injections of cocaine (10 mg/kg, i.p.) resulted in locomotor sensitization for LCRs, but not HCRs; nonetheless, all rats exhibited decreased latency to acquire cocaine self-administration compared to the first experiment. Repeated cocaine preexposure and LCR/HCR classification predicted break point when rats responded for cocaine under a progressive ratio schedule of reinforcement (0.25, 0.5, and 1.0 mg/kg/infusion; multiple exposure>single exposure, LCR>HCR), but there was no interaction between these variables. CONCLUSIONS Although LCR/HCR classification did not predict the rate of acquisition of cocaine self-administration under these conditions, LCR rats demonstrated greater responding for cocaine after acquisition (PR). Thus, these findings demonstrate the relevance of using the LCR/HCR model when studying susceptibility to cocaine dependence.
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Affiliation(s)
- Bruce H. Mandt
- University of Colorado Denver, Department of Pharmacology, Aurora, CO
| | - Susan Schenk
- Victoria University of Wellington, School of Psychology, Wellington, New Zealand
| | - Nancy R. Zahniser
- University of Colorado Denver, Department of Pharmacology, Aurora, CO,University of Colorado Denver, Neuroscience Program, Aurora, CO
| | - Richard M. Allen
- University of Colorado Denver, Department of Psychology, Denver, CO
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Plawecki MH, Han JJ, Doerschuk PC, Ramchandani VA, O'Connor SJ. Physiologically based pharmacokinetic (PBPK) models for ethanol. IEEE Trans Biomed Eng 2008; 55:2691-700. [PMID: 19126448 PMCID: PMC3446827 DOI: 10.1109/tbme.2008.919132] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Physiologically based pharmacokinetic models have been used to describe the distribution and elimination of ethanol after intravenous administration. These models have been used to estimate the ethanol infusion profile that is sufficient for achieving a prescribed breath ethanol concentration time course in individuals, providing a useful platform for several pharmacokinetic and pharmacodynamic investigations. Mathematical foundations of these models are examined, including the derivation of an explicit set of governing equations in the form of a system of nonlinear ordinary differential equations. These equations can then be used to formulate and refine parameter identification and control strategies. Finally, a framework in which models related to this model can be constructed and analyzed is described.
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Slutske WS, D'Onofrio BM, Turkheimer E, Emery RE, Harden KP, Heath AC, Martin NG. Searching for an environmental effect of parental alcoholism on offspring alcohol use disorder: a genetically informed study of children of alcoholics. JOURNAL OF ABNORMAL PSYCHOLOGY 2008; 117:534-51. [PMID: 18729607 DOI: 10.1037/a0012907] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The children-of-twins design was used to isolate a potentially causal environmental impact of having an alcoholic parent on offspring alcohol use disorder, by an examination of whether the children of alcoholics were at a higher risk for alcohol use disorders than were the children of nonalcoholic parents, even after correlated familial factors were controlled. Participants were 1,224 male and female twins from 836 twin pairs selected from the Australian Twin Registry, 2,334 of the twins' 18-39-year-old offspring, and 983 spouses of the twins. Lifetime histories of Diagnostic and Statistical Manual of Mental Disorders (4th ed.) alcohol use disorders were obtained by structured, psychiatric, telephone interviews conducted individually with each of the family members. Comparisons of the offspring of twins who were discordant for alcoholism indicated that there was no longer a statistically significant difference between the children of alcoholics and the children of nonalcoholics after genetic and family environmental factors correlated with having an alcoholic parent were controlled. The results of this study suggest that the direct causal effect of being exposed to an alcoholic parent on offspring alcohol use disorder is modest at best.
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Affiliation(s)
- Wendy S Slutske
- Department of Psychological Sciences, Midwest Alcoholism Research Center, University of Missouri-Columbia, Columbia, MO 65211, USA.
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18
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Duranceaux NCE, Schuckit MA, Luczak SE, Eng MY, Carr LG, Wall TL. Ethnic differences in level of response to alcohol between Chinese Americans and Korean Americans. J Stud Alcohol Drugs 2008; 69:227-34. [PMID: 18299763 DOI: 10.15288/jsad.2008.69.227] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE Koreans have higher rates of alcohol-use disorders and family history of alcoholism, compared with Chinese. These differences likely reflect both environmental and genetic influences. One genetically influenced characteristic that may contribute to these ethnic differences is level of response to alcohol. Variant alleles of aldehyde dehydrogenase (ALDH2) and alcohol dehydrogenase (ADH1B) genes are prevalent in individuals of Asian heritage and have been associated with an increased level of response to alcohol and a decreased risk for alcohol dependence. Additionally, a low level of response to alcohol is more common in individuals with a first-degree family history of alcoholism and is predictive of increased risk for this disorder. It also is possible that sociocultural factors have an impact on an individual's response to alcohol. The current study examined self-report level of response to alcohol, ALDH2 and ADH1B, country of origin, and family history of alcoholism in 154 Chinese- and 181 Korean-American college students. METHOD Participants were evaluated via in-person interviews and genotyped at the ALDH2 and ADH1B loci. RESULTS Ethnicity was significantly related to level of response to alcohol, with Koreans having a lower self-reported level of response than Chinese. This relationship remained significant after considering the effects of gender, height, weight, quantity and frequency of alcohol consumption (over the previous 90 days), ALDH2 genotype, ADH1B genotype, country of origin, and first-degree family history of alcohol dependence. CONCLUSIONS The results suggest that a low level of response to alcohol may contribute to the increased risk for alcohol abuse and dependence found in Koreans, relative to Chinese. More research is needed to determine additional factors that may be contributing to the low alcohol response and high rates of alcoholism in Koreans.
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Le Strat Y, Gorwood P. Does lower response to alcohol explain the high co-morbidity between bipolar disorder and alcohol dependence? Med Hypotheses 2008; 71:81-4. [PMID: 18394813 DOI: 10.1016/j.mehy.2008.02.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Revised: 02/08/2008] [Accepted: 02/13/2008] [Indexed: 11/18/2022]
Abstract
The frequency of the co-occurrence between alcohol use disorders and bipolar disorder is well documented. However, the etiology of this association is discussed. Among the most quoted hypothesis, high alcohol consumption has been considered as a form of self-medication. At variance with this assumption, we hypothesized that mania is associated with a low level of response to alcohol. Indeed, a low level of response to alcohol was previously associated with an increased risk of alcohol dependence in a high risk population. We discuss the neurobiological findings supporting our assumption, including the decreased reward-related brain activation in mania and further propose a brief study design to test this hypothesis.
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Affiliation(s)
- Y Le Strat
- INSERM U675, IFR02, Faculté de Médecine Xavier Bichat/Université Paris 7, 16 Rue Henri Huchard, 75018 Paris, France
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20
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Schramm-Sapyta NL, Kingsley MA, Rezvani AH, Propst K, Swartzwelder HS, Kuhn CM. Early ethanol consumption predicts relapse-like behavior in adolescent male rats. Alcohol Clin Exp Res 2008; 32:754-62. [PMID: 18336637 DOI: 10.1111/j.1530-0277.2008.00631.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Alcohol abuse disorders emerge over time with repeated consumption of ethanol, but not all ethanol drinkers develop these disorders. There are pre-existing characteristics that indicate which drinkers are most likely to abuse alcohol. Adolescence, novelty seeking, and high stress reactivity are among the characteristics of the most vulnerable individuals. In addition, an individual's response to his or her first exposure to the drug influences future consumption. We assessed an array of behavioral and hormonal characteristics in adolescent (28-day-old) male rats before exposure to ethanol, and then determined which rats were most prone to high levels of alcohol drinking. METHODS The assessments consisted of measures of anxiety (elevated plus maze), response to novelty (open field locomotion, novel object exploration), and circulating corticosterone levels after mild restraint and after the elevated plus maze task. After this test battery, the rats were placed in lickometer cages nightly (5 pm to 9 am) for evaluation of fluid consumption. Rats were first habituated to the cages with water in the lickometer bottles, and then given 10% (v/v) ethanol for 3 nights as the only available fluid. After this forced ethanol exposure, the rats were allowed to choose between 8% ethanol and water for 10 consecutive nights. After 2 nights of abstinence, the rats were again placed in the lickometer cages and given a choice between 8% ethanol and water to assess ethanol consumption in response to alcohol deprivation, a measure of relapse-like behavior. RESULTS Ethanol consumption on the third day of forced consumption was significantly correlated with ethanol consumption on days 8 to 10 of the choice phase, which in turn was significantly correlated to relapse-like consumption. Preference for ethanol was also significantly correlated with early consumption. Novel object exploration, open field activity, open arm time in the elevated plus maze, initial water consumption, and circulating corticosterone levels did not significantly predict deprivation-stimulated consumption. CONCLUSIONS These results suggest that consumption during early exposure to ethanol establishes a pattern leading to development of increased alcohol consumption and preference in adolescent male rats. In addition, they represent an animal model of the well-described observation that humans who consume large quantities of ethanol during early exposure are the most likely to repeat heave drinking behavior. Furthermore, early consumption is distinct from novelty seeking, anxiety, and stress hormone levels which are also thought to contribute to vulnerability to alcoholism.
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Affiliation(s)
- Nicole L Schramm-Sapyta
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710, USA
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Plawecki MH, Decarlo R, Ramchandani VA, O'Connor S. IMPROVED TRANSFORMATION OF MORPHOMETRIC MEASUREMENTS FOR A PRIORI PARAMETER ESTIMATION IN A PHYSIOLOGICALLY-BASED PHARMACOKINETIC MODEL OF ETHANOL. Biomed Signal Process Control 2007; 2:97-110. [PMID: 18379641 PMCID: PMC2180397 DOI: 10.1016/j.bspc.2007.04.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Prescription of the brain's time course of exposure to experimentally administered ethanol can be achieved with intravenous infusion profiles computed from a physiologically-based pharmacokinetic (PBPK) model of alcohol distribution and elimination. Previous parameter estimation employed transformations of an individual's age, height, weight and gender inferred from the literature, with modeling errors overcome with real-time, intermittent feedback. Current research applications, such as ethanol exposures administered during fMRI scanning, require open-loop infusions, thus improved transformation of morphometric measurements.Records of human breath alcohol concentration (BrAC) clamp experiments were analyzed. Optimal, unique PBPK parameters of a model of the distribution and elimination of ethanol were determined for each record and found to be in concordance with parameter values published by other investigators. A linear transformation between the readily measurable physical characteristics or morphometrics, including gender, age, height, weight, and TBW estimates, and the model parameters were then determined in a least squares sense according to the formula theta=F(x)=F(m)x where x=(age height weight TBW)(T)inR(4) and theta =(R(C) V(P) V(B) m(max)k(AT))(T)inR(5).The transformation was then evaluated with several parameter prediction performance measures. A substantial improvement in all error statistics, in relation to an earlier affine transformation that used only body weight as the relevant morphometric was obtained. Deviation from the measured response was reduced from 27 to 20%. Error in parameter estimation was reduced from 109 to 38%. Percent alcohol provided in error was reduced from 46 to 28%. Error in infusion profile estimation was reduced from 55 to 33%.The algorithm described, which optimizes individual pharmacokinetic parameter values and then subsequent extension to a priori prediction, while not unique, can be readily be adapted to other molecules and pharmacokinetic models. This includes those used for distinct purposes, such as automated control of anesthetic agents.
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Affiliation(s)
- Martin H Plawecki
- Purdue University Weldon School of Biomedical Engineering, West Lafayette, IN 47906
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Allen RM, Everett CV, Nelson AM, Gulley JM, Zahniser NR. Low and high locomotor responsiveness to cocaine predicts intravenous cocaine conditioned place preference in male Sprague-Dawley rats. Pharmacol Biochem Behav 2006; 86:37-44. [PMID: 17250883 PMCID: PMC2712248 DOI: 10.1016/j.pbb.2006.12.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2006] [Revised: 11/29/2006] [Accepted: 12/12/2006] [Indexed: 10/23/2022]
Abstract
Outbred, male Sprague-Dawley rats can be classified as either low or high cocaine responders (LCRs or HCRs, respectively) based on cocaine-induced locomotor activity in an open-field arena. This difference reflects cocaine's ability to inhibit the striatal dopamine transporter and predicts development of sensitization. To investigate the relationship between initial cocaine locomotor responsiveness and cocaine reward, here we first classified rats as either LCRs or HCRs in a conditioned place preference (CPP) apparatus. Subsequently, we conducted cocaine conditioning trials, twice-daily over 4 days with vehicle and cocaine (10 mg/kg, i.p. or 1 mg/kg, i.v.). When cocaine was administered by the i.p. route, similar to previous findings in the open-field, LCRs and HCRs were readily classified and locomotor sensitization developed in LCRs, but not HCRs. However, cocaine CPP was not observed. In contrast, when cocaine was administered by the i.v. route, the LCR/HCR classification not only predicted sensitization, but also CPP, with only LCR rats exhibiting sensitization and cocaine conditioning. Our findings show that the initial locomotor response to cocaine can predict CPP in male Sprague-Dawley rats under conditions when place conditioning develops, and that LCRs may be more prone to develop conditioning in the context of cocaine reward.
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Affiliation(s)
- Richard M Allen
- Department of Psychology, University of Colorado at Denver and Health Sciences Center, CB 173, PO Box 173364, Denver, CO 80217, USA.
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