GPR22 is an orphan G protein-coupled receptor (GPCR). It is involved in ciliogenesis in zebrafish, and shows a highly restricted expression pattern in humans and rodents, with abundant and selective expression in the brain and heart. GPR22 protein expression has been detected in cardiac myocytes and coronary arteries by immunohistochemistry. It has been hypothesized to have a protective role for in response to hemodynamic stress resulting from increased afterload in the heart. References: PLOS One/doi.org/10.1371/journal.pone.0110484; 01 AUG 2008https://doi.org/10.1152/ajpheart.00368.2008