Orexin Receptor 1 Antibodies
OX1 receptors are G protein-coupled receptors whose orthologs are present throughout mammals. OX1 expression in CNS includes brainstem nuclei involved in arousal and sleep/wake regulation as well as nuclei involved in reward signaling. Orexin-A and -B neuropeptides have different affinities for OX1 receptors (IC50s of 20 and 420 nM, respectively). Receptor activation results in elevated intracellular calcium levels mediated by Gq and phospholipase C activation, but contributions from Gs- and Gi-mediated regulation of cAMP levels as well as non-selective cation channels have also been described. OX1 receptor signaling in sleep/wake regulation is not as well defined as for OX2 receptors, but has been implicated in mood, anxiety, memory and reward, with mixed effects on feeding reported. OX1 receptor desensitization, β-arrestin recruitment and internalization are regulated by phosphorylation of carboxyl-terminal serine385(pS385-OX1), serine393/serine394 (pS393/pS394-OX1) and serine399/serine401 (pS399/pS401-OX1). This nomenclature refers to the human OX1. This phosphorylation motif is conserved across species but corresponds to pS384/pS385-OX1 and pS390/pS392-OX1 in mice and rats. For more information on OX1 pharmacology please refer to the IUPHAR database. For further reading refer to:
Scammell TE, Winrow CJ. Orexin receptors: pharmacology and therapeutic opportunities. Annu Rev Pharmacol Toxicol. 2011;51:243-66. doi: 10.1146/annurev-pharmtox-010510-100528. PMID: 21034217
Coleman P, de Lecea L, Gotter A, Hagan J, Hoyer D, Kilduff T, Kukkonen JP, Porter R, Renger J, Siegel JM, Sutcliffe G, Upton N, Winrow CJ. Orexin receptors (version 2019.3) in the IUPHAR/BPS Guide to Pharmacology Database. IUPHAR/BPS Guide to Pharmacology CITE. 2019; 2019(3). Available from: https://doi.org/10.2218/gtopdb/F51/2021.3.