What is the difference between Orexin A and hypocretin-1?

They are the same molecule; orexin and hypocretin were independently named by two research groups around the same time.

Why is Orexin A linked to narcolepsy?

Narcolepsy type 1 results from loss of orexin-producing neurons, so the peptide is central to research on wakefulness and sleep regulation.

How is it studied for delivery to the brain?

Intranasal delivery is commonly used in research because it can reach the central nervous system more directly than peripheral routes.

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Cognitive & Nootropic

Research Chemical

Orexin A

Also known as: Orexin A, Hypocretin-1

A 33-amino-acid neuropeptide produced in the lateral hypothalamus that regulates wakefulness, arousal, appetite and energy homeostasis. It is studied for its powerful promotion of alertness and sleep-wake stability.

Mechanism of Action

Orexin A (hypocretin-1) binds both orexin receptor subtypes OX1R and OX2R, which are G-protein-coupled receptors that depolarize target neurons and increase intracellular calcium. Through OX2R it strongly stabilizes wakefulness by activating histaminergic, noradrenergic and dopaminergic arousal circuits. It also modulates feeding behavior, reward signaling and autonomic tone. Loss of orexin neurons is the underlying cause of narcolepsy type 1, which frames its central role in maintaining wakefulness.

Half-life: Short; on the order of minutes to roughly an hour depending on route
Administration Routes: intranasal, subcutaneous
Research Status: Research Chemical