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Ethanol preference, a component of alcoholism, has been known for four decades to differ greatly between C57BL/6 and BALB/c inbred mouse strains. For mapping quantitative trait loci (QTLs) that affect ethanol preference, we used a set of B6.C Recombinant QTL Introgression (RQI) strains, which carry about 5% of the donor BALB/cJ (C) genome on a C57BL/6ByJ (B6) background. After characterizing males of the progenitor and RQI strains for variations in ethanol preference, we scanned their genome for polymorphisms at 244 dinucleotide-repeat marker loci known to differ between B6 and C. Because of the introgression of BALB/c-type QTLs onto the B6 background, some strains showed ethanol preference significantly lower or higher than that of the background strain, suggesting that genetic interaction between ethanol preference QTLs and the background can be operative. The genomic region showing the strongest influence on ethanol preference was on mouse chromosome 15, and corresponds to human chr.12q11-q13.

Epidemiological studies have reported a reduction in the prevalence of Alzheimer's disease in individuals that ingest low amounts of alcohol. Also, it has been found that moderate consumption of ethanol might protect against β-amyloid (Aβ) toxicity. However, the mechanism underlying its potential neuroprotection is largely unknown. In the present study, we found that ethanol improved the cognitive processes of learning and memory in 3xTgAD mice. In addition, we found that a low concentration of ethanol (equivalent to moderate ethanol consumption) decreased the binding of Aβ (1 and 5 μM) to neuronal membranes and, consequently, its synaptotoxic effect in rat hippocampal and cortical neurons under acute (30 minutes) and chronic (24 hours) incubation conditions. This effect appears to be exerted by a direct action of ethanol on Aβ because electron microscopy studies showed that ethanol altered the degree of Aβ aggregation. The action of ethanol on Aβ also prevented the peptide from perforating the neuronal membrane, as assayed with patch clamp experiments. Taken together, these results contribute to elucidating the mechanism by which low concentrations of ethanol protect against toxicity induced by Aβ oligomers in primary neuronal cultures. These results may also provide an explanation for the decrease in the risk of Alzheimer's disease in people who consume moderate doses of alcohol.

An ambulatory monitor has been used to determine the characteristic patterns of tremor, sweating, skin temperature and locomotor activity in subjects undergoing alcohol withdrawal. Twenty-four hour records were obtained from six male subjects who had been consuming an average of 345 g of alcohol per day prior to cessation and from a group of age-matched controls. Consistent with earlier research and clinical observation, tremor, sweating and locomotor activity were elevated in withdrawal subjects. Sweating was greatest in the period from approximately 00.00 h to 06.00 h, as was skin temperature. Tremor and activity levels decreased during this period, but were considerably higher in withdrawal subjects. The data suggest that 24-h monitoring of alcohol withdrawal using objective methods provides a more sensitive assessment technique than the standard clinical approaches. The technique may be of value in other dysautonomic states.

AbstractThe SPACE volume selection technique was combined with a spin‐echo sequence to measure the transverse relaxation time of the resonances of ethanol and cerebral metabolites in the dog brain, in vivo. The method was extended to measure brain metabolite T2, values in the rat using 1H NMR microspectroscopy. The T2 decays for the resonances of the metabolites N‐acetylaspartate, creatine/phosphocreatine, and choline/phosphorylcholine were found to be biexponential with long T2 components of 490, 260, and 350 ms for the dog and 490, 220, and 355 ms for the rat brain, respectively. The existence of a second T2 component may originate from J‐coupled nonresolved metabolite resonances. The relaxation decay for the ethanol triplet could be fitted to a single exponential giving a T2 relaxation time of 335 ms. However, given the large errors in the measurement of ethanol peak intensities at short echo times because of overlapping lipid signal and the effects of J‐modulation, a biexponential decay with a long T2 component of 335 ms cannot be ruled out. Ambiguities regarding the reported partial detection of the 1H NMR signal of ethanol in the brain are discussed. © 1992 Academic Press, Inc.

This article presents the proceedings of the symposium "Endogenous Opioids and Voluntary Ethanol Consumption: What Have We Learnt From Knock-out Mice?" presented at the meeting of the International Society for Biomedical Research on Alcoholism held in Heidelberg/Mannheim, Germany, in September/October 2004. The organizers and chairpersons were Michael S. Cowen and Carles Sanchis-Segura. The presentations were as follows: (1) Regulation of the Opioid System by Alcohol: Comparison of Alcohol-Preferring and -Nonpreferring Strains by Michael S. Cowen; (2) Endogenous Opioids and Alcohol: Lessons From Microdialysis and Knock-out Mice by M. Foster Olive; (3) From Neurochemistry to Neuroanatomy: The Hypothalamic Arcuate Nucleus as a Main Site for Ethanol-Opioids Interaction by Carles Sanchis-Segura; (4) Sensitivity to Ethanol Is Modulated by beta-Endorphin in Transgenic Mice by Judy E. Grisel, Amanda J. Roberts, and George F. Koob; and () The mu-Opioid Receptor Modulates Acute Ethanol Sensitivity and Ethanol Withdrawal Severity by Sandra Ghozland.

AbstractAlcohol use disorders represent an extensive socioeconomic burden, yet effective treatment options are suboptimal. A major hurdle in treating alcohol use disorders is the high rate of relapse. Stress is a major factor that promotes relapse in abstinent drug users; therefore, understanding neural mechanisms that underpin the effects of stress on alcohol seeking is critical. In rodent models of stress‐induced relapse, the α2‐adrenoceptor antagonist, yohimbine, is a widely used chemical stressor to elicit reinstatement of drug/alcohol seeking. However, the exact mechanism how yohimbine precipitates reinstatement of alcohol seeking and the pattern of neural activation associated with yohimbine‐induced reinstatement is poorly understood. Therefore, we counted Fos‐protein positive nuclei across 42 brain regions in alcohol‐experienced alcohol preferring rats that received either yohimbine in the home‐cage (1 mg/kg i.p.) or following yohimbine‐induced reinstatement of alcohol seeking. The number of Fos‐protein positive nuclei was increased in the prefrontal cortex and extended amygdala after home‐cage yohimbine compared to naïve‐ and vehicle‐treated rats. Yohimbine‐induced reinstatement increased the number of Fos‐protein expressing nuclei in multiple other regions including the thalamus, hypothalamus and hippocampus. We then examined inter‐regional correlations in Fos‐protein expression for all 42 brain regions, which showed Fos expression was more strongly positively correlated following yohimbine‐induced reinstatement of alcohol seeking, compared to home‐cage yohimbine. These data suggest low‐dose yohimbine in a non‐drug‐associated context activates stress/impulsivity centres within the brain, whereas yohimbine in the drug‐associated context recruits additional brain regions to drive alcohol seeking.

Maternal alcohol consumption throughout pregnancy can result in long term behavioural deficits in offspring. However, less is known about the impact of alcohol during the periconceptional period (PC). The aim of this study was to examine the effect of PC ethanol (PC:EtOH) exposure on long term cognitive function; including memory and anxiety. Rats were exposed to a liquid diet containing ethanol (EtOH) (12.5% vol;vol) or a control diet from 4 days prior to mating until day 4 of pregnancy. Separate cohorts of animals were tested at 6 months (adult) or 15-18 months of age (aged). Offspring underwent a series of behavioural tests to assess anxiety, spatial and recognition memory. The hippocampus was collected, and mRNA expression of epigenetic modifiers and genes implicated in learning and memory were examined. PC:EtOH exposure resulted in a subtle anxiety like behaviour in adult female offspring with a significant reduction in directed exploring/head dipping behaviour during holeboard testing. In aged male offspring, PC:EtOH exposure resulted in a tendency for increased directed exploring/head dipping behaviour during holeboard testing. No differences between treatments were observed in the elevated plus maze. Aged female offspring exposed to PC:EtOH demonstrated short term spatial memory impairment (P < 0.05). PC:EtOH resulted in an upregulation of hippocampal mRNA expression of bdnf, grin2a and grin2b at 18 months of age along with increased expression of epigenetic modifiers (dnmt1, dnmt3a and hdac2). In conclusion, PC:EtOH can lead to sex specific anxiety-like behaviour and impairments in spatial memory and altered hippocampal gene expression.

Two new lines of rats have been selectively bred for high or low active avoidance responding--the Australian High (AHA) and Low (ALA) Avoiders. Ethanol (1-1.5 g/kg body weight, i.p.) improved acquisition of active avoidance responding only in ALA, whereas alpha-methyl-p-tyrosine (AMPT; 80 mg/kg body weight, i.p.) seemed to selectively impair acquisition of responding in AHA. The combination of ethanol and AMPT caused a general depression of behaviour. The 2 lines did not differ consistently in the latency to escape from shock, locomotor activity, 'emotionality' or passive avoidance responding. Ethanol had no effect on locomotor activity or 'emotionality', but increased the latency to escape from shock and impaired passive avoidance responding in both lines.