Cloning and expression of a cDNA for rat prostacyclin receptor.

A cDNA clone for rat prostacyclin receptor was isolated. The cDNA encodes a protein of 416 amino acid residues (M(r) 44,662) with putative seven transmembrane domains, and belongs to the G protein-coupled receptor superfamily. Specific binding of [3H]iloprost was found in membrane of COS-7 cells transfected with the cDNA (Kd = 1.3 nM) and was displaced with unlabeled prostaglandins in the order of iloprost = cicaprost > PGE1 > STA2 = PGE2 = PGD2 > PGF2 alpha. Northern blot analysis demonstrated that rat prostacyclin receptor mRNA is expressed in the lung, spleen, heart, pancreas, thymus, stomach and aorta.