Chronic alcohol drinking and subsequent withdrawal in rats exposed to different diurnal distributions of schedule-induction sessions.

Eight rats drank large amounts of 6.25% alcohol as a consequence of daily exposure to 6 hours of schedule-induction sessions in which a small food pellet was delivered every 90 sec. Rats having a 1-hr session every 4 hr showed slightly more withdrawal distress than rats having a 6-hr session every 24 hr. More significant may have been two different kinds of indication of possible loss of control over drinking by the inducing schedule. Rats experiencing six sessions a day did not drink water excessively when it replaced the alcohol solution. Rats experiencing one session a day drank half their total alcohol intake between sessions. If the schedule-induction procedure loses control over alcohol drinking, its chronic application to animals fails as a model of the factors that maintain excessive alcohol use in humans.