Male BRAF^fl/fl/Cre^+/− (BRAF) or wild-type (WT) mice were treated with corn-oil vehicle (CO) or tamoxifen in CO (Tx) 4 days before minipumps (MP) were implanted to deliver acidified PBS (AcPBS) or 0.8 mg/kg/d AngII. Mice were sacrificed after 1 or 7 d. Echocardiograms were collected and hearts taken at 7 d. (A) Schematic of experimental protocol. (B) Representative M-mode echocardiograms taken from short axis views of the hearts of BRAF^fl/fl/Cre^+/− at 7 d. (C) Analysis of echocardiograms taken at 7 d to assess cardiac dimensions. Abbreviations: EDV, end diastolic volume; EDLVM, end diastolic left ventricular mass; LVID, left ventricle internal diameter; LVWT, left ventricle wall thickness (posterior plus anterior walls). LVID and LVWT were measured at diastole from M-mode images of short axis views of the heart. EDV and EDLVM were predicted from B-mode images of long axis views of the heart. (D) Haematoxylin and eosin staining of mouse heart sections (left panels) from hearts collected at 7 d, with assessment of cardiomyocyte cross-sectional area (CSA; right panel). Images and measurements are from the periphery of the left ventricle. (E,F) mRNA expression in mouse hearts after 24 h (E) or 7 d (F) treatment with AngII. RNA was extracted and expression of Nppa, Nppb, Myh7 and Edn1 were assessed by qPCR. Data are individual values with means ± SEM. Statistical analysis used two-way ANOVA with Holm-Sidak’s post-test. Statistically significant values (P<0.05) are in bold type.