Rationale: Acute alcohol effects may differ in social drinkers with a positive family history of alcohol use disorders (FHP) compared to FH negative (FHN) controls.
Objectives: To investigate whether FHP subjects prefer higher levels of brain alcohol exposure than do FHN controls.
Materials and methods: Twenty-two young healthy nondependent social drinkers participated in two identical sessions of computer-assisted self-infusion of ethanol (CASE); the first for practicing the procedures, the second to test hypotheses. All 12 FHP (four women) and ten FHN (three women) participants received a priming exposure, increasing arterial blood alcohol concentration (aBAC) to 30 mg% at 10 min and decreasing it to 15 mg% at 25 min. A 2-h self-administration period followed, during which only the subjects could increase their aBAC by pressing a button connected to a computer controlling the infusion pump. Infusion rate profiles were calculated instantaneously to increase aBAC by precisely 7.5 mg% within 2.5 min after each button press, followed by a steady descent. Subjects were instructed to produce the same alcohol effects as they would do at a weekend party.
Results: The mean and maximum aBAC during the self-administration period and the number of alcohol requests (NOAR) were significantly higher in the FHP vs. FHN participants.
Conclusions: This is the first laboratory experiment demonstrating higher alcohol self-administration in FHP compared to FHN subjects. A practice session increases the sensitivity of CASE experiments for detection of subtle differences in human alcohol self-administration.