Intake of individual macronutrients following IP injections of BBS and CCK in rats

The effects of injections of either bombesin (BBS) or cholecystokinin octapeptide (CCK-8) on patterns of food intake of macronutrients were examined in adult male rats, and compared to the effects following saline injections. The animals were food deprived for 18 hours and then offered one of three isocaloric dietary components (protein, carbohydrate or fat). During the first 30 minutes following injections of BBS, protein intake was decreased. Suppression of carbohydrate intake, significant between 30 and 60 minutes, was sustained up to two hours following injections. During the first 30 minutes following injections of CCK, animals reduced their intake of each macronutrient. Reductions in the consumption of fat and protein were sustained up to one and six hours, respectively. The availability of particular macronutrients is proposed as a possible factor accounting for differences among studies with respect to self-selection profiles and duration effects.