Influence of Age and Sex on Alcohol Metabolism and Acute Responses

This study will examine age and sex differences in alcohol metabolism and the effects of alcohol. Men and women differ in their ability to metabolize alcohol, possibly due to differences between men and women in lean body mass, liver size, or the activity of enzymes that act on alcohol in the liver. Also, older men and women are thought to be more sensitive to alcohol, although the reasons for this are not clear. Healthy men and women between 21 and 25 years of age and between 55 and 65 years of age who are social drinkers may be eligible for this study. Candidates will be screened with questionnaires about their general and mental health, alcohol use, and family history of alcohol use and problems. They will have a physical examination, electrocardiogram (EKG), routine blood tests, urinalysis to test for drugs of abuse, and a blood test to study the gene responsible for enzymes that metabolize alcohol. Younger women will have a urine pregnancy test and older women will have a test to confirm post-menopausal status. Participants will have two study sessions at the NIH Clinical Center outpatient clinic. They come to the clinic by taxi and, upon arrival, take a breathalyzer test for any measurable alcohol levels. They are then given breakfast, after which two catheters (plastic tubes) are placed, one in a vein in each arm. One tube is used to collect blood samples for measuring hormone levels; the other is for infusing alcohol. The infusion is adjusted so that the breath alcohol level is held constant for about 3 hours at a moderate level. Baseline measurements are taken before the infusion begins. During and after the infusion, the participants fill out questionnaires about their moods and feelings. Breath alcohol level and heart rate measurements are monitored frequently. After the test, participants remain in the clinic until their breath alcohol level drops below 0.02 g/L (generally 2 to 3 hours after the infusion stops). They are given lunch and then sent home