Target family: Hydroxycarboxylic acid receptors (type: gpcr)
Target: HCA<sub>1</sub> receptor

Ligand: nicotinic acid (Metabolite)
Interaction type: Agonist
Action: Agonist
Ligand approved: no
Primary target: no
Median affinity:  -
Reference (Journal): Molecular identification of high and low affinity receptors for nicotinic acid.
Published in: J Biol Chem

Ligand: L-lactic acid (Metabolite)
Interaction type: Agonist
Action: Full agonist
Ligand approved: no
Median affinity:  pEC50
Reference (Journal): Role of GPR81 in lactate-mediated reduction of adipose lipolysis.
Published in: Biochem Biophys Res Commun

Ligand: L-lactic acid (Metabolite)
Interaction type: Agonist
Action: Full agonist
Ligand approved: no
Median affinity:  pEC50
Reference (Journal): An autocrine lactate loop mediates insulin-dependent inhibition of lipolysis through GPR81.
Published in: Cell Metab

Ligand: L-lactic acid (Metabolite)
Interaction type: Agonist
Action: Full agonist
Ligand approved: no
Median affinity:  pEC50
Reference (Journal): Lactate inhibits lipolysis in fat cells through activation of an orphan G-protein-coupled receptor, GPR81.
Published in: J Biol Chem

Ligand: L-lactic acid (Metabolite)
Interaction type: Agonist
Action: Full agonist
Ligand approved: no
Median affinity:  pEC50
Reference (Journal): Screening β-Arrestin Recruitment for the Identification of Natural Ligands for Orphan G-Protein-Coupled Receptors.
Published in: J Biomol Screen

Ligand: L-lactic acid (Metabolite)
Interaction type: Agonist
Action: Full agonist
Ligand approved: no
Median affinity:  pEC50
Reference (Journal): Lactate inhibits lipolysis in fat cells through activation of an orphan G-protein-coupled receptor, GPR81.
Published in: J Biol Chem

Ligand: L-lactic acid (Metabolite)
Interaction type: Agonist
Action: Full agonist
Ligand approved: no
Median affinity:  pEC50
Reference (Journal): An autocrine lactate loop mediates insulin-dependent inhibition of lipolysis through GPR81.
Published in: Cell Metab

Ligand: γ-hydroxybutyrate (Metabolite)
Interaction type: Agonist
Action: Full agonist
Ligand approved: yes
Approval source: FDA (2002), EMA (2005)
Median affinity: 1.82 pEC50
Reference (Journal): Lactate inhibits lipolysis in fat cells through activation of an orphan G-protein-coupled receptor, GPR81.
Published in: J Biol Chem

Ligand: D-lactic acid (Metabolite)
Interaction type: Agonist
Action: Partial agonist
Ligand approved: no
Median affinity: 2.52 pEC50
Reference (Journal): Role of GPR81 in lactate-mediated reduction of adipose lipolysis.
Published in: Biochem Biophys Res Commun

Ligand: compound 2 [PMID: 31932225] (Synthetic organic)
Interaction type: Agonist
Action: Agonist
Ligand approved: no
Primary target: no
Median affinity: 7.130000114440918 pEC50
Reference (Journal): Involvement of the metabolic sensor GPR81 in cardiovascular control.
Published in: JCI Insight

Ligand: compound 2 [PMID: 31932225] (Synthetic organic)
Interaction type: Agonist
Action: Agonist
Ligand approved: no
Primary target: no
Median affinity: 7.130000114440918 pEC50
Reference (Journal): Identification of novel GPR81 agonist lead series for target biology evaluation.
Published in: Bioorg Med Chem Lett

Ligand: compound 2 [PMID: 24486398] (Synthetic organic)
Interaction type: Agonist
Action: Agonist
Ligand approved: no
Primary target: no
Median affinity: 7.239999771118164 pEC50
Reference (Journal): Identification of a novel GPR81-selective agonist that suppresses lipolysis in mice without cutaneous flushing.
Published in: Eur J Pharmacol

Ligand: 3,5-dihydroxybenzoic acid (Synthetic organic)
Interaction type: Agonist
Action: Full agonist
Ligand approved: no
Median affinity: 3.72 pEC50
Reference (Journal): 3,5-Dihydroxybenzoic acid, a specific agonist for hydroxycarboxylic acid 1, inhibits lipolysis in adipocytes.
Published in: J Pharmacol Exp Ther