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orexin (ORX),

Neuropeptide involved in neuroendocrine function including feeding and drinking behavior; two subtypes, A and B, exist.


Either of two neuropeptide hormones synthesized in the hypothalamus that regulate sleep and wakefulness and whose dysfunction causes narcolepsy. Also called hypocretin.


A class of hypothalamic neuropeptide hormones that regulates sleep cycles and energy expenditure; they probably do not directly affect appetite, as was once believed.


One of a pair of centrally-acting neuropeptides produced by the lateral hypothalamus where the sensation of hunger is mediated. Rats given orexin will eat about ten times the normal amount of food and rats starved for 48 hours have more than twice the normal concentrations of orexin. There are also specific receptors for the two orexins. These facts are being exploited in the design of drugs that can both stimulate and reduce appetite.
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Lemborexant, a dual orexin receptor antagonist, is Eisai's in-house discovered and developed small molecule compound that inhibits orexin neurotransmission by binding competitively to the two subtypes of orexin receptors (orexin receptor 1 and 2).
Lemborexant, a dual orexin receptor antagonist, is an in-house discovered novel small molecule which inhibits orexin by binding competitively to two subtypes of orexin receptors (orexin receptor 1 and 2).
The cause of this overactivity is not clear but may be driven by certain adipokines, signaling cytokines produced by adipose tissue (including orexin, leptin, free fatty acids, tumor necrosis factor, interleukin-6, C-reactive protein, angiotensinogen, and adiponectin).
2011), we named the three candidates Air-CCAPR1-Like (similar to cardioacceleratory peptide receptor), Air-AAR1-Like (similar to allatostatin-A receptor), and Air-OX2R1-Like (similar to orexin receptor type 2).
Orexin A is 33 amino acid long and has two intrachain disulfide bonds while Orexin B is a linear 28 amino acid residue peptide.
The nonbenzodiazepine hypnotics eszopiclone and Zolpidem as well as the orexin receptor antagonist suvorexant improved short-term sleep quality, though the effect was small and there was significant evidence of harm as described above.
Table 1 11 Pharmacological domains Acetylcholine Dopamine GABA Glutamate Histamine Ion channel Melatonin Norepinephrine Opioid Orexin Serotonin Table 2 9 Modes of action Enzyme inhibitor Enzyme modulator Ion channel blocker Neurotransmitters releaser Positive allosteric modulator Receptor agonist Receptor antagonist Receptor partial agonist Reuptake inhibitor
US Food and Drug Administration (FDA)-approved hypnotic medications fall into 5 families (TABLE 2(40)): benzodiazepines (BDZs), benzodiazepine agonists (BDZAs, sometimes called "Z drugs"), melatonin agonists (eg, ramelteon), tricyclic antidepressants (eg, low-dose doxepin), and orexin antagonists (eg, suvorexant).
Impaired orexin receptor expression in the Kolliker-Fuse nucleus in sudden infant death syndrome: possible involvement of this nucleus in arousal pathophysiology.
Global Markets Direct's, 'Orexin Receptor Type 2 (Ox2R or Hypocretin Receptor Type 2 or HCRTR2) - Pipeline Review, H1 2016', provides in depth analysis on Orexin Receptor Type 2 (Ox2R or Hypocretin Receptor Type 2 or HCRTR2) targeted pipeline therapeutics.
Orexins--also known as hypocretins, are neuropeptides synthesized in the posterolateral hypothalamus, and are represented by Orexin A and Orexin B.
The hypothalamic neuropeptide orexin is released into the accumbens and SB334867, an orexin-1 receptor antagonist, inhibits relapse in rodents.