Cholecystokinin and bombesin act independently to decrease food intake in the rat.

Area of Science:

• Neuroscience
• Gastroenterology
• Endocrinology

Background:

• Peptides like cholecystokinin-octapeptide (CCK-8) and bombesin (BBS) are known to influence feeding behavior.
• Understanding the mechanisms of satiety is crucial for addressing eating disorders and obesity.

Purpose of the Study:

• To compare the satiating effects of CCK-8 and BBS when administered alone and in combination.
• To investigate whether CCK-8 and BBS act via additive or independent mechanisms to induce satiety.

Main Methods:

• Intact rats were administered varying doses of CCK-8 and BBS, alone and in combination.
• Food intake was measured over a 30-minute period following injections.

Main Results:

• Both CCK-8 and BBS demonstrated a dose-dependent reduction in food intake.
• CCK-8 was more potent than BBS in inducing satiety, with a 4 µg/kg dose suppressing intake by 72%.
• BBS reached maximal suppression of approximately 40% at 2 µg/kg.
• Combined administration resulted in additive suppression of food intake, equivalent to the sum of individual effects.

Conclusions:

• CCK-8 and BBS appear to act through independent pathways to regulate satiety.
• The findings support a model of peptidergic satiety where distinct mechanisms mediate the effects of these peptides.