The orexin receptor (also referred to as the hypocretin receptor) is a G-protein-coupled receptor that binds the neuropeptide hormone orexin. There are two variants, OX1 and OX2, each encoded by a different gene (HCRTR1, HCRTR2).[1]
Both orexin receptors exhibit a similar pharmacology - the 2 orexin peptides, orexin-A and orexin-B, bind to both receptors and, in each case, agonist binding results in an increase in intracellular calcium levels. However, orexin-B shows a 10-fold selectivity for orexin receptor type 2, whilst orexin-A is equipotent at both receptors.[2]
Several orexin receptor antagonists are in development for potential use in sleep disorders.
[edit] References
- ^ Spinazzi R, Andreis PG, Rossi GP, Nussdorfer GG (2006). "Orexins in the regulation of the hypothalamic-pituitary-adrenal axis". Pharmacol. Rev. 58 (1): 46–57. doi:10.1124/pr.58.1.4. PMID 16507882.
- ^ Smart D, Jerman JC, Brough SJ, Rushton SL, Murdock PR, Jewitt F, Elshourbagy NA, Ellis CE, Middlemiss DN, Brown F (September 1999). "Characterization of recombinant human orexin receptor pharmacology in a Chinese hamster ovary cell-line using FLIPR". Br. J. Pharmacol. 128 (1): 1–3. doi:10.1038/sj.bjp.0702780. PMC 1571615. PMID 10498827.
[edit] External links
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Class A:
Rhodopsin like |
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Metabolites and
signaling molecules
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Peptide
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Miscellaneous
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| Class B: Secretin like |
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Class C: Metabotropic
glutamate / pheromone |
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Class F:
Frizzled / Smoothened |
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B trdu: iter (nrpl/grfl/cytl/horl), csrc (lgic, enzr, gprc, igsr, intg, nrpr/grfr/cytr), itra (adap, gbpr, mapk), calc, lipd; path (hedp, wntp, tgfp+mapp, notp, jakp, fsap, hipp, tlrp)
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| Cholecystokinin |
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| CRH |
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| Galanin |
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| Ghrelin |
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| GnRH |
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| MCH |
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| Melanocortin |
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| Neuropeptide S |
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| Neuropeptide Y |
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| Neurotensin |
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| Orexin |
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| Oxytocin |
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| Tachykinin |
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- Agonists: Substance P
Antagonists: Aprepitant
- Befetupitant
- Casopitant
- CI-1021
- CP-96,345
- CP-99,994
- CP-122,721
- Dapitant
- Ezlopitant
- FK-888
- Fosaprepitant
- GR-203,040
- GW-597,599
- HSP-117
- L-733,060
- L-741,671
- L-743,310
- L-758,298
- Lanepitant
- LY-306,740
- Maropitant
- Netupitant
- NKP-608
- Nolpitantium
- Orvepitant
- RP-67,580
- SDZ NKT 343
- Vestipitant
- Vofopitant
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| Vasopressin |
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This article incorporates text from the public domain Pfam and InterPro IPR004060
