Central thermoregulatory effects of neuropeptide Y and orexin A in rats

Orexin A and neuropeptide Y that are known to induce a feeding response when applied centrally, in the present studies also caused hypothermia. Neuropeptide Y elicited hypothermia by depressing metabolic rate (without affecting heat loss mechanisms), while orexin A acted through enhancing peripheral heat loss (without affecting metabolic rate). Neither peptide induced coordinated thermoregulatory changes, both of them appeared to influence thermoregulation via different effector mechanisms.