Ethanol consumption by C57BL/6 mice: Influence of gender and procedural variables

Both sexes of C57BL/6 (C57) mice consumed substantial quantities of ethanol without food or water deprivation whether access was continuous or limited . Food deprivation increased the amount of ethanol consumed, and the amount consumed depended upon when the animals were tested with reference to thei r daily food allotment. Ethanol consumption was greater if the mice were te sted postprandially, high thirst motivation, rather than preprandially (sim ilar to 10 vs. similar to 4.5 g/kg/30 min). Preference for ethanol over wat er, however, was greater when mice were under low thirst motivation (i.e., tested preprandially or with water available during the test). Compared to males, female mice consumed more of a high-ethanol concentration solution ( 10%) when access was continuous or limited to the first hour of the dark (a ctive) phase of the circadian cycle. Also, in contrast to males, female mic e exhibited increased ethanol consumption across days of drinking experienc e. Finally, although ethanol consumption under the food deprivation conditi ons of this experiment did not differ according to sex, females had higher blood ethanol concentrations than male C57 mice, a finding not previously r eported for rodents but common to humans. (C) 1999 Elsevier Science Inc. Al l rights reserved.