| Primary Identifier | IPR028016 | Type | Family |
| Short Name | HCAR1_rcpt |
| description | The hydroxycarboxylic acid receptors []are members of the rhodopsin-like G protein-coupled receptor (GPCR) family. There are three hydroxycarboxylic acid receptors, termed HCAR1-3. The family was formerly known as nicotinic acid receptor family, although nicotinic acid only shows submicromolar potency at HCAR2 [, ].The receptors respond to organic acids, including the endogenous short chain fatty acids, butyric acid and L-lactic acid, as well as the lipid lowering agents nicotinic acid (niacin), acipimox and acifran [, , ]. There is an increasing number of synthetic ligands mainly targeted at HCAR2 and HCAR3 receptors [, ]. All three receptors are expressed in adipocytes, and are coupled to Gi type G-proteins mediating antilipolytic effects in fat cells [, , , ]. HCAR2 and HCAR3 are also expressed in a variety of immune cells including monocytes, macrophages, neutrophils and Langerhans cells [, ]. HCAR1 and HCAR2 are found in most mammalian species, whereas HCAR3 is only present in higher primates []. There is evidence that these receptors can mediate anti-inflammatory effects. HCAR2 has been shown to be a receptor for the anti-dyslipidemic drug nicotinic acid (niacin) as well as for the anti-psoriatic drug monomethyl-fumarate [, ]. This entry represents hydroxycarboxylic acid receptor 1, also known as lactate receptor 1, G protein coupled receptor 104 and G-protein coupled receptor 81. The endogenous ligand for HCAR1 is L-lactic acid []. |
