title: Moderate alcohol exposure during early brain development increases stimulus-response habits in adulthood.
abstract: Exposure to alcohol during early central nervous system development has been shown variously to affect aspects of physiological and behavioural development. In extreme cases, this can extend to craniofacial defects, severe developmental delay and mental retardation. At more moderate levels, subtle differences in brain morphology and behaviour have been observed. One clear effect of developmental alcohol exposure is an increase in the propensity to develop alcoholism and other addictions. The mechanisms by which this occurs, however, are not currently understood. In this study, we tested the hypothesis that adult zebrafish chronically exposed to moderate levels of ethanol during early brain ontogenesis would show an increase in conditioned place preference for alcohol and an increased propensity towards habit formation, a key component of drug addiction in humans. We found support for both of these hypotheses and found that the exposed fish had changes in mRNA expression patterns for dopamine receptor, nicotinic acetylcholine receptor and μ-opioid receptor encoding genes. Collectively, these data show an explicit link between the increased proclivity for addiction and addiction-related behaviour following exposure to ethanol during early brain development and alterations in the neural circuits underlying habit learning.
authors.affiliation: School of Biological and Chemical Sciences, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, UK.
authors.forename: Matthew O
authors.initials: MO
authors.lastname: Parker
authors.affiliation: School of Biological and Chemical Sciences, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, UK.
authors.forename: Alexandra M-D
authors.initials: AM
authors.lastname: Evans
authors.affiliation: School of Biological and Chemical Sciences, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, UK.
authors.forename: Alistair J
authors.initials: AJ
authors.lastname: Brock
authors.affiliation: School of Biological and Chemical Sciences, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, UK.
authors.forename: Fraser J
authors.initials: FJ
authors.lastname: Combe
authors.affiliation: Centre for Clinical and Diagnostic Oral Sciences, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, UK.
authors.forename: Muy-Teck
authors.initials: MT
authors.lastname: Teh
authors.affiliation: School of Biological and Chemical Sciences, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, UK.
authors.forename: Caroline H
authors.initials: CH
authors.lastname: Brennan
mesh_terms: D000437:Alcoholism; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001921:Brain / Q000187:drug effects* / Q000196:embryology; D002492:Central Nervous System Depressants / Q000494:pharmacology*; D002755:Choice Behavior / Q000187:drug effects; D003213:Conditioning, Psychological / Q000187:drug effects; D004195:Disease Models, Animal; D047108:Embryonic Development; D000431:Ethanol / Q000494:pharmacology*; D005260:Female; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012333:RNA, Messenger / Q000187:drug effects* / Q000378:metabolism; D011954:Receptors, Dopamine / Q000187:drug effects / Q000235:genetics; D011978:Receptors, Nicotinic / Q000187:drug effects / Q000235:genetics; D017450:Receptors, Opioid, mu / Q000187:drug effects / Q000235:genetics; D015027:Zebrafish
chemical_list: D002492:Central Nervous System Depressants; D012333:RNA, Messenger; D011954:Receptors, Dopamine; D011978:Receptors, Nicotinic; D017450:Receptors, Opioid, mu; D000431:Ethanol
keywords: CPP; addiction; dopamine; habit; moderate prenatal ethanol; zebrafish; μ-opioid