Orexin A Peptide

Overview

Orexin A (Hypocretin-1) is a naturally occurring endogenous neuropeptide composed of 33 amino acid residues with a C-terminal amidation and two critical intra-molecular disulfide bonds. Produced primarily in the lateral hypothalamic area, Orexin A acts as a crucial regulatory signaling ligand across both Orexin-1 (OX1R) and Orexin-2 (OX2R) receptors, playing a pivotal role in maintaining wakefulness, regulating appetite, and driving energy expenditure.

Key Functional Areas & Mechanism of Action

• Sleep-Wake Architecture & Arousal: Serves as a master molecular switch in the central nervous system to stabilize wakefulness and inhibit rapid eye movement (REM) sleep transitions, making it a primary compound in narcolepsy and hypersomnia research.

• Dual Receptor Affinity (OX1R / OX2R): Binds non-selectively with nanomolar affinity to both G-protein coupled orexin receptors, initiating intracellular calcium mobilization and downstream neuro-excitatory cascades.

• Energy Homeostasis & Feeding Behavior: Modulates central feeding circuitry, stimulates autonomic nervous system activation, and influences basal metabolic rate and lipolysis.

• Neuro-Cognitive Signaling: Interacts with dopaminergic, noradrenergic, and histaminergic pathways to regulate alertness, reward mechanisms, and stress responses.