Effects of chlordiazepoxide on schedule-induced water and alcohol consumption in the squirrel monkey.

Lever pressing of five squirrel monkeys was maintained by a 3-min fixed-interval schedule of food presentation. 3 monkeys had water concurrently available and, for a second pair of monkeys, initially water, then increasing concentrations of alcohol (1--3% v/v) were present. Substantial amounts of post-pellet drinking occurred with all five monkeys. The amount of water ingested was approximately 100 ml per session, that of 3% alcohol nearly 63 ml. For the monkeys drinking alcohol, increasing concentrations of alcohol decreased both the rate of lever pressing and the volume of fluid consumed. Chlordiazepoxide (1.0--17.0 mg/kg) produced increases in lever pressing and in the schedule-induced consumption of both 3% alcohol and water.