hydroxycarboxylic acid receptor

The hydroxycarboxylic acid receptor (abbreviated HCA receptor and HCAR) family includes the following human proteins:{{cite journal | vauthors = Offermanns S | title = Free fatty acid (FFA) and hydroxy carboxylic acid (HCA) receptors | journal = Annual Review of Pharmacology and Toxicology | volume = 54 | issue = | pages = 407–34 | date = 2014 | pmid = 24160702 | doi = 10.1146/annurev-pharmtox-011613-135945 | url = | doi-access = free }}

• Hydroxycarboxylic acid receptor 1 (HCA₁, formerly known as GPR81)
• Hydroxycarboxylic acid receptor 2 (HCA₂, formerly known as niacin receptor 1 and GPR109A)
• Hydroxycarboxylic acid receptor 3 (HCA₃, formerly known as niacin receptor 2 and GPR109B)