A) Timeline of angiotensin II (AngII) infusion experimental protocol. DOX, doxycycline administration. B) Heart weight-to-tibia length ratio (HW/TL) of αMHC-tTA and TRE-NCLX x αMHC-tTA mice 2 weeks after sham or angiotensin II minipump implantation surgery. Data analyzed by 2-way ANOVA with Sidak’s post-hoc test. #P<0.05, ###P<0.001 vs. sham. (n=5–10 mice / group). C) Left ventricular tissue 2 weeks after sham or angiotensin II minipump implantation surgery, stained with wheat germ agglutinin (WGA, red) to delineate sarcolemma and with DAPI (blue). Scale bars = 50 µm. D) Quantification of cardiomyocyte cross-sectional area (CSA). Data analyzed by 2-way ANOVA with Sidak’s post-hoc test. ##P<0.01 vs. sham. (n=5–10 mice / group). E-G) qPCR quantification of mRNA expression of fetal genes in hearts of αMHC-tTA and TRE-NCLX x αMHC-tTA mice 2 weeks after sham or angiotensin II minipump implantation surgery. Nppa, natriuretic peptide type A; Nppb, natriuretic peptide type b; Myh6, α-myosin heavy chain; Myh7, β-myosin heavy chain. Data analyzed by 2-way ANOVA with Sidak’s post-hoc test. ##P<0.01, ###P<0.001, ####P<0.0001 vs. sham. (n=5–10 mice / group).