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for educational and safety purposes
Orexin-A and Orexin-B both come up in the same conversations; they overlap on Orexin and Wakefulness. Orexin-A: Orexin-A, also known as hypocretin-1, is a 33-amino-acid neuropeptide produced by a small population of neurons in the lateral hypothalamus that is central to promoting wakefulness and arousal. Orexin-B: Orexin-B, also known as hypocretin-2, is a 28-amino-acid neuropeptide made in the hypothalamus that, together with orexin-A, promotes wakefulness, arousal, and appetite.
Orexin-A, also known as hypocretin-1, is a 33-amino-acid neuropeptide produced by a small population of neurons in the lateral hypothalamus that is central to promoting wakefulness and arousal. It is one of two orexin peptides cut from a single precursor and signals through two G-protein-coupled receptors. Narcolepsy type 1 is essentially an orexin-deficiency disease, in which the roughly 70,000 orexin-producing neurons are selectively destroyed and cerebrospinal-fluid orexin becomes undetectable; this is the rationale for orexin-2 receptor agonists now in clinical trials as the first mechanism-based, replacement-style treatment rather than a symptomatic stimulant. Since its discovery in 1998 the orexin system has become a major target in sleep medicine.
Orexin-B, also known as hypocretin-2, is a 28-amino-acid neuropeptide made in the hypothalamus that, together with orexin-A, promotes wakefulness, arousal, and appetite. It is cut from the same precursor as orexin-A but lacks internal disulfide bonds and preferentially activates the orexin type 2 receptor. That receptor is the target of the dual orexin receptor antagonists suvorexant, lemborexant, and daridorexant, which treat insomnia by blocking the same signaling whose loss causes narcolepsy, making the two conditions pharmacological mirror images; one of these drugs was also reported to acutely lower tau and amyloid-beta in human cerebrospinal fluid. The orexin system was discovered in 1998.
both fingerprints on one instrument; where the marks line up the two compounds work the same lever, where a slot goes dark only one of them touches it. read straight from each entry's affinity table; nothing here is invented.
Agonist
Weak agonist
Agonist
Agonist
Activation
Activation
strengths are the entries' qualitative ratings (strong / moderate / weak); Ki and EC50 figures appear where an entry records them.