Galectin-3 loss does not affect diastolic dysfunction, fibrosis, and cardiomyocyte hypertrophy in the pressure-overloaded myocardium. A–F: Doppler echocardiography and tissue Doppler imaging shows that galectin-3 absence does not affect diastolic function. TAC increases (A) and peak E (B) and A (C) velocities in both WT and galectin-3 KO mice. The E/A ratio is significantly reduced in WT mice after 56 days of TAC (D). The E/E′ ratio, a sensitive indicator of diastolic dysfunction, increases after TAC in both WT and galectin-3 KO mice (E), whereas the E′/A′ ratio is reduced (F). Galectin-3 loss has no effects on indicators of diastolic dysfunction. G–J: Sirius red staining was used to label collagen fibers in WT and galectin-3 KO hearts after 28 days of TAC. No statistically significant difference was noted between WT and KO mice (H) in both male and female groups. K–N: Cardiomyocyte size was assessed in sections stained for WGA lectin. Cardiomyocyte size was comparable in WT and galectin-3 KO mice after 28 days of TAC (L), in both male and female mice. Data are expressed as means ± SEM. n = 10 to 16 per group (A–F); n = 9 to 10 per group (K–N). *P < 0.05, **P < 0.01 versus corresponding pre. Scale bar = 60 μm. Bpm, beats per minute; HR, heart rate; KO, knockout; TAC, transverse aortic constriction; WT, wild-type.