PLN and Myocardial fibrosis: Histological analysis of cardiac tissue at 8 weeks of age using Masson’s trichrome staining showed no difference in fibrosis between WT and PLN-R14Δ/+ mice, whereas in PLN-R14Δ/Δ mice extensive myocardial fibrosis was present throughout the LV and right ventricle (RV) (Fig. 2C,D).