[Alcohol drinking behavior based on the neurochemical background. II. Alcohol preference and aging].

The present studies have investigated the relationship between alcohol behavior and aging in several strains of mice. First experiments have carried out whether a free choice of 10% (v/v) ethanol and tap water for 4 weeks changes the alcohol preference and the brain neurotransmitters in three inbred strains of mice, C57BL/6J, C3H/He and DBA/2Cr. Mice of these strains showed mean ethanol intakes of 4.41, 1.76 and 0.77 g/kg/day, respectively. Levels of the brain monoamines did not change in the alcohol preferring C57BL/6J mice, but in those with less preference of alcohol, C3H/He and DBA/2Cr, there were significant increases in dopamine and 5HT levels during the four weeks experiment. Second studies have reexamined if the factor of aging affects on the alcohol preference or drinking behavior in mice. Intake of 10% ethanol (ml/day) and alcohol preference (%) increased significantly with age. A further study was conducted in which groups of 16 week old mice were checked for alcohol preference along with a completely naive control group. The alcohol preference and alcohol intake were maximum in mice given free access to ethanol at 4 weeks of age. These results suggest that a) the mouse strain with a low preference of alcohol undergo neurochemical changes after exposure to 10% ethanol and water even be free choice, and b) alcohol drinking behaviors are not only affected on the general aspects but also the factor of aging and the conditions in which mice have expressed the accesses to alcohol.