The effects of cocaine on food intake of baboons before, during, and after a period of repeated desipramine.

Food intake of five adult male baboons (Papio c. anubis) was monitored during daily 22-hr experimental sessions. Food was available under a chain schedule with two components. Following completion of the "procurement" component, the first response requirement, access to food, i.e., a meal, became available under the second, "consumption" component, during which each response produced a 1 g food pellet. After a 10-min interval in which no response occurred, the consumption component was terminated. Complete dose-response functions for cocaine (0.50-4.0 mg/kg, IM) and desipramine (0.50-4.0 mg/kg, IM), were determined before, during, and after a period of repeated administration of desipramine. Cocaine produced dose-dependent increases in the latency to initiate feeding and decreases in food intake during the first eight hr of the session. Compensatory feeding occurred later in the session so that cocaine had no effect on total daily intake. There was no interaction between repeated desipramine and the acute effects of cocaine. Desipramine produced dose-dependent decreases in intake during the first two hr of the session, the size of the first meal and intake during the entire session. These measures, as well as number of meals and second meal size, remained below baseline during repeated desipramine. Thus, repeated desipramine, while having significant effects on feeding behavior itself, did not influence the effects of cocaine administration on food-maintained responding.