ChEMBL ligand: CHEMBL3932722
OX1 receptor/Orexin/Hypocretin receptor type 1 in Human [ChEMBL: CHEMBL5113] [GtoPdb: 321] [UniProtKB: O43613] There should be some charts here, you may need to enable JavaScript!
OX2 receptor/Orexin receptor type 2 in Human [ChEMBL: CHEMBL4792] [GtoPdb: 322] [UniProtKB: O43614] There should be some charts here, you may need to enable JavaScript!

DB	Assay description	Assay Type	Standard value	Standard parameter	Original value	Original units	Original parameter	Reference
OX1 receptor/Orexin/Hypocretin receptor type 1 in Human (target type: SINGLE PROTEIN) [ChEMBL: CHEMBL5113] [GtoPdb: 321] [UniProtKB: O43613]
ChEMBL	Displacement of 3H-SB-674042 from human Ox1R expressed in CHO cell membranes by liquid scintillation counting method	B	7.74	pKi	18.2	nM	Ki	Bioorg Med Chem Lett (2024) 100: 129629-129629 [PMID:38295907]
ChEMBL	Displacement of 3H-SB-674042 from human Ox1R expressed in CHO cell membranes by liquid scintillation counting method	B	7.74	pKi	18.2	nM	Ki	Bioorg Med Chem Lett (2024) 100: 129629-129629 [PMID:38295907]
GtoPdb	-	-	7.9	pKi	12.6	nM	Ki	Nat Metab (2022) 4: 1495-1513 [PMID:36411386]
ChEMBL	Antagonist activity at human Ox1R overexpressed in rat Chem-1 cells assessed as inhibition of orexin A induced calcium flux preincubated for 15 mins followed by orexin A addition by FLIPR analysis	F	7.8	pIC50	16	nM	IC50	Bioorg Med Chem Lett (2024) 100: 129629-129629 [PMID:38295907]
ChEMBL	Fluorescent Imaging Plate Reader (FLIPR) Assay: Orexin antagonist activity was determined by measuring changes in intracellular calcium levels using a Ca2+ sensitive fluorescent dye. The changes in fluorescent signal were monitored by Fluorescent Imaging Plate Reader (FLIPR®) technology available from Molecular Devices, LLC, U.S.A. Orexin mediated increases in intracellular Ca2+ concentration were readily detected upon activation with orexin-A. Twenty-four hours prior to the assay, RBL-2H3 cells stably expressing either human orexin receptor 1 or human orexin receptor 2 were seeded in cell culture medium in black, clear-bottom 384-well plates (commercially available from Corning Inc., U.S.A.) and grown overnight at 37 °C., 5% CO2. On the day of the assay, cell culture media was removed and cells were loaded with Calcium 5 Dye (commercially sold by Molecular Devices, LLC, U.S.A.) for 1 hour at 37 °C., 5% CO2.	F	7.92	pIC50	12	nM	IC50	US-9156829-B2. Cycloalkyl and heterocycloalkyl compounds as orexin receptor antagonists (2015)
ChEMBL	FLIPR Assay: Orexin antagonist activity was determined by measuring changes in intracellular calcium levels using a Ca2+ sensitive fluorescent dye. The changes in fluorescent signal were monitored by Fluorescent Imaging Plate Reader (FLIPR) technology available from Molecular Devices, LLC, U.S.A. Orexin mediated increases in intracellular Ca2+ concentration were readily detected upon activation with orexin-A. Twenty-four hours prior to the assay, RBL-2H3 cells stably expressing either human orexin receptor 1 or human orexin receptor 2 were seeded in cell culture medium in black, clear-bottom 384-well plates (commercially available from Corning Inc., U.S.A.) and grown overnight at 37° C., 5% CO2. On the day of the assay, cell culture media was removed and cells were loaded with Calcium 5 Dye (commercially sold by Molecular Devices, LLC, U.S.A.) for 1 hour at 37° C., 5% CO2. Test compounds (at 10 point half log concentration response curves from 10 μM) were added to cells for 15 minutes prior to the addition of orexin-A to all wells, to achieve a final concentration that produces approximately an 80% maximal response.	B	7.92	pIC50	12	nM	IC50	US-10011588-B2. 1,2-substituted cyclopentanes as orexin receptor antagonists (2018)
ChEMBL	FLIPR Assay: Orexin antagonist activity was determined by measuring changes in intracellular calcium levels using a Ca2+ sensitive fluorescent dye. The changes in fluorescent signal were monitored by Fluorescent Imaging Plate Reader (FLIPR™) technology available from Molecular Devices, LLC, U.S.A. Orexin mediated increases in intracellular Ca2+ concentration were readily detected upon activation with orexin-A. Twenty-four hours prior to the assay, RBL-2H3 cells stably expressing either human orexin receptor 1 or human orexin receptor 2 were seeded in cell culture medium in black, clear-bottom 384-well plates (commercially available from Corning Inc., U.S.A.) and grown overnight at 37° C., 5% CO2. On the day of the assay, cell culture media was removed and cells were loaded with Calcium 5 Dye (commercially sold by Molecular Devices, LLC, U.S.A.) for 1 hour at 37° C., 5% CO2. Test compounds (at 10 point half log concentration response curves from 10 μM) were added to cells for 15 minutes prior to the addition of orexin-A to all wells, to achieve a final concentration that produces approximately an 80% maximal response.	B	7.92	pIC50	12	nM	IC50	US-10689373-B2. 1,2-substituted cyclopentanes as orexin receptor antagonists (2020)
OX2 receptor/Orexin receptor type 2 in Human (target type: SINGLE PROTEIN) [ChEMBL: CHEMBL4792] [GtoPdb: 322] [UniProtKB: O43614]
GtoPdb	-	-	4.66	pKi	21880	nM	Ki	Nat Metab (2022) 4: 1495-1513 [PMID:36411386]
ChEMBL	Binding affinity to Ox2R (unknown origin)	B	4.66	pKi	21877.62	nM	Ki	Bioorg Med Chem Lett (2024) 100: 129629-129629 [PMID:38295907]
ChEMBL	Fluorescent Imaging Plate Reader (FLIPR) Assay: Orexin antagonist activity was determined by measuring changes in intracellular calcium levels using a Ca2+ sensitive fluorescent dye. The changes in fluorescent signal were monitored by Fluorescent Imaging Plate Reader (FLIPR®) technology available from Molecular Devices, LLC, U.S.A. Orexin mediated increases in intracellular Ca2+ concentration were readily detected upon activation with orexin-A. Twenty-four hours prior to the assay, RBL-2H3 cells stably expressing either human orexin receptor 1 or human orexin receptor 2 were seeded in cell culture medium in black, clear-bottom 384-well plates (commercially available from Corning Inc., U.S.A.) and grown overnight at 37 °C., 5% CO2. On the day of the assay, cell culture media was removed and cells were loaded with Calcium 5 Dye (commercially sold by Molecular Devices, LLC, U.S.A.) for 1 hour at 37 °C., 5% CO2.	F	5	pIC50	>10000	nM	IC50	US-9156829-B2. Cycloalkyl and heterocycloalkyl compounds as orexin receptor antagonists (2015)
ChEMBL	FLIPR Assay: Orexin antagonist activity was determined by measuring changes in intracellular calcium levels using a Ca2+ sensitive fluorescent dye. The changes in fluorescent signal were monitored by Fluorescent Imaging Plate Reader (FLIPR) technology available from Molecular Devices, LLC, U.S.A. Orexin mediated increases in intracellular Ca2+ concentration were readily detected upon activation with orexin-A. Twenty-four hours prior to the assay, RBL-2H3 cells stably expressing either human orexin receptor 1 or human orexin receptor 2 were seeded in cell culture medium in black, clear-bottom 384-well plates (commercially available from Corning Inc., U.S.A.) and grown overnight at 37° C., 5% CO2. On the day of the assay, cell culture media was removed and cells were loaded with Calcium 5 Dye (commercially sold by Molecular Devices, LLC, U.S.A.) for 1 hour at 37° C., 5% CO2. Test compounds (at 10 point half log concentration response curves from 10 μM) were added to cells for 15 minutes prior to the addition of orexin-A to all wells, to achieve a final concentration that produces approximately an 80% maximal response.	B	5	pIC50	>10000	nM	IC50	US-10011588-B2. 1,2-substituted cyclopentanes as orexin receptor antagonists (2018)
ChEMBL	FLIPR Assay: Orexin antagonist activity was determined by measuring changes in intracellular calcium levels using a Ca2+ sensitive fluorescent dye. The changes in fluorescent signal were monitored by Fluorescent Imaging Plate Reader (FLIPR™) technology available from Molecular Devices, LLC, U.S.A. Orexin mediated increases in intracellular Ca2+ concentration were readily detected upon activation with orexin-A. Twenty-four hours prior to the assay, RBL-2H3 cells stably expressing either human orexin receptor 1 or human orexin receptor 2 were seeded in cell culture medium in black, clear-bottom 384-well plates (commercially available from Corning Inc., U.S.A.) and grown overnight at 37° C., 5% CO2. On the day of the assay, cell culture media was removed and cells were loaded with Calcium 5 Dye (commercially sold by Molecular Devices, LLC, U.S.A.) for 1 hour at 37° C., 5% CO2. Test compounds (at 10 point half log concentration response curves from 10 μM) were added to cells for 15 minutes prior to the addition of orexin-A to all wells, to achieve a final concentration that produces approximately an 80% maximal response.	B	5	pIC50	>10000	nM	IC50	US-10689373-B2. 1,2-substituted cyclopentanes as orexin receptor antagonists (2020)

ChEMBL data shown on this page come from version 36:

Zdrazil B, Felix E, Hunter F, Manners EJ, Blackshaw J, Corbett S, de Veij M, Ioannidis H, Lopez DM, Mosquera JF, Magarinos MP, Bosc N, Arcila R, Kizilören T, Gaulton A, Bento AP, Adasme MF, Monecke P, Landrum GA, Leach AR. (2024). The ChEMBL Database in 2023: a drug discovery platform spanning multiple bioactivity data types and time periods. Nucleic Acids Res., 52(D1). DOI: 10.1093/nar/gkad1004. [EPMCID:10767899] [PMID:37933841]
Davies M, Nowotka M, Papadatos G, Dedman N, Gaulton A, Atkinson F, Bellis L, Overington JP. (2015) 'ChEMBL web services: streamlining access to drug discovery data and utilities.' Nucleic Acids Res., 43(W1). DOI: 10.1093/nar/gkv352. [EPMCID:25883136]