The role of prostanoids in cardiac hypertrophy has been examined using animal models of pressure overload- and angiotensin II (Ang II)-infusion.107,108 One example is PGI2 as it (and its analogues) can inhibit the Ang II-induced hypertrophy of cultured cardiomyocytes,107 as well as the proliferation and synthesis of collagen by cultured cardiac fibroblasts.109,110 In a more pathophysiologically relevant situation, the PGI2-IP system attenuated the development of pressure overload-induced cardiac hypertrophy by inhibiting both cardiomyocyte hypertrophy and cardiac fibrosis. This evidence concerns the gene AGT and cardiac hypertrophy.