Bombesin stimulates insulin secretion and reduces food intake in the baboon

Baboons received a 5-minute intravenous infusion of either saline or bombesin (BBS; 1-4 micrograms/kg) following 3 1/2 or 16 1/2 hours of food deprivation and were then allowed to eat for 30 minutes. Plasma insulin was significantly elevated following five minutes of BBS infusion, but there was no change of plasma glucose over the same interval. Bombesin infusion resulted in a dose-dependent decrease of food intake that was independent of deprivation time. Plasma insulin levels following the 30-minute meal were significantly depressed after BBS infusions such that there was essentially no change of plasma insulin over the duration of the meal, even though the baboons did not totally suppress their food intake. Following 3 1/2 hours food deprivation, BBS suppressed the post-prandial rise of plasma glucose in a dose-dependent manner. The results provide further evidence that BBS and/or structurally-related peptides are involved in the regulation of feeding and metabolism.