Cholecystokinin and bombesin suppress operant responding for food reward

The effects of intraperitoneal injections of cholecystokinin (CCK) and bombesin (BBS) on food-rewarded operant responding were investigated. Response rates were significantly suppressed following administrations of CCK (0.7, 1.4, and 2.9 micrograms/kg). The effects appeared to be dose dependent. Responding was also suppressed following injections of BBS (6 and 16 micrograms/kg). These results confirm and extend previous findings concerning the possible function of these peptides.