PTGS2 and Myocardial fibrosis: Targeted disruption of the COX-2 gene in COX-2-knockout mice or selective deletion of COX-2 in cardiomyocytes has been shown to contribute to myocardial fibrosis and myocardial I/R injury (Dinchuk et al. 1995; Camitta et al. 2001; Papanicolaou et al. 2010).