Orexin A (human, rat, mouse) acetate (205640-90-0 Free base), a 33 amino acid excitatory neuropeptide, orchestrates diverse central and peripheral processes. Orexin A (human, rat, mouse) acetate has been used to study its effect on the functioning of porcine pancreatic islets. Orexin A (human, rat, mouse) acetate has also been used as an orexin receptor 1 (OX1R) agonist to study the effect of orexin systems in the effect of etonogestrel on respiratory response to prolonged metabolic acidosis.