Intracerebroventricular injection of orexin-A stimulates monoamine metabolism but not HPA axis in neonatal chicks

▶ Intracerebroventricular injection of orexin-A induced arousal in neonatal chicks. ▶ The hypothalamic-pituitary-adrenal axis activity was not concerned this function. ▶ Several monoaminergic systems appear to be involved in arousal-inducing mechanisms.