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Brain regional gamma-aminobutyric acid type A (GABAA) receptor subunit mRNA expression was studied in ethanol-preferring AA (Alko, Alcohol) rats after moderate ethanol drinking for up to 2 years of age. In situ hybridization with oligonucleotide probes specific for 13 different subunits was used with coronal cryostat sections of the brains. Selective alterations were observed by ethanol exposure and/or aging in signals for several subunits. Most interestingly, the putative highly ethanol-sensitive alpha4 and beta3 subunit mRNAs were significantly decreased in several brain regions. The age-related alterations in alpha4 subunit expression were parallel to those caused by lifelong ethanol drinking, whereas aging had no significant effect on beta3 subunit expression. The results suggest that prolonged ethanol consumption leading to blood concentrations of about 10 mM may downregulate the mRNA expression of selected GABAA receptor subunits and that aging might have partly similar effects.

Background: Although the beneficial effects of mild to moderate ethanol consumption have been implied with respect to heart, alcohol abuse has proven to be a major cause of nonischemic cardiomyopathy in Western society. However, the biochemical and molecular mechanisms, which mediate the pathologic cardiac effects of ethanol, remain largely unknown. The aim of the present study was to explore the effects of chronic ethanol exposure on cardiac apoptosis and expression of some of the genes associated with cardiac remodeling in vivo., Methods: Alcohol-avoiding Alko Non Alcohol rats of both sexes were used. The ethanol-exposed rats (females, n=6; males, n=8) were given 12% (v/v) ethanol as the only available fluid from age of three to 24 months of age. The control rats (females, n=7; males, n=5) had only water available. At the end of the experiment, free walls of left ventricles of hearts were immediately frozen. Cytosolic DNA fragmentation, reflecting apoptosis, was measured using a commercial quantitative sandwich enzyme-linked immunosorbent assay kit, and mRNA levels were analyzed using a quantitative reverse transcriptase-polymerase chain reaction method., Results: Ethanol treatment for two years increased cardiac left ventricular p53 mRNA levels significantly (p=0.014) compared with control rats. The gene expression was also dependent on the gender (p=0.001), so that male rats had higher left ventricular p53 mRNA levels than female rats. However, no significant differences in levels of DNA fragmentation were detected., Conclusions: Chronic ethanol exposure in vivo induces rat cardiac left ventricular p53 gene expression. Expression of p53 is also gender-dependent, males having higher p53 mRNA levels than females. This preliminary finding suggests a role for the p53 gene in ethanol-induced cardiac remodeling. The results might also have some relevance for the known gender-dependent differences in propensity to cardiovascular disease.

The purpose of the present study was to examine the combined effects of aging and lifelong ethanol exposure on the levels of monoamine neurotransmitters in different regions of the brain. This work is part of a project addressing interactions of aging and lifelong ethanol consumption in alcohol-preferring AA (Alko Alcohol) line of rats, selected for high voluntary consumption of ethanol. Intake of ethanol on the level of 4.5-5 g/kg/day for about 20 months induced only limited changes in the neurotransmitter levels; the concentration of noradrenaline was significantly reduced in the frontal cortex. There was also a trend towards lower levels of dopamine and 5-hydroxytryptamine (5-HT) in the frontal cortex, and towards a lower noradrenaline level in the dorsal cortex. Aging was associated with a decreased concentration of dopamine in the dorsal cortex and with a declining trend in the striatum. The levels of 5-HT in the limbic forebrain were higher in the aged than in the young animals, and in the striatum, there was a trend towards higher levels in older animals. The data suggest that a continuous intake of moderate amounts of ethanol does not enhance the age-related alterations in brain monoamine neurotransmission, while the decline in the brain level of dopamine associated with aging may be a factor contributing to age-related neurological disorders. [ABSTRACT FROM AUTHOR]