[Bombesin reduces body temperature chiefly by increasing peripheral blood flow]

Bombesin, some of its fragments and analogues, being injected intracerebroventricularly, induce rapid decline in body temperature. The active fragment of bombesin--C-terminal nonapeptide--induced a 25% depression of oxygen consumption in cold-exposed rabbits, no changes in the shivering thermogenesis, and a 3.5--5.0-fold increase of ear blood vessels section area accompanied by a gain in linear velocity of blood flow. The peripheral blood flow seems to be the main effector of the bombesin-induced hypothermia.