<i>H-Bmal1</i>^−/− mice develop progressive congestive heart failure with age.

<p>(A) Representative gross morphology of hearts from 12-week-old control and <i>H-Bmal1</i>^−/− mice. (B) Ratios of heart weight to body weight (HW/BW) at 12 weeks of age (n = 6 per group). (C) Low-power views after H&E staining of transverse sections from control and <i>Bmal1</i>^−/− hearts at 12 weeks of age. (D) LV lateral wall thickness determined in histological images used in (C) (n = 5 per group). (E) Echocardiographic analysis in 12-week-old control and <i>H-Bmal1</i>^−/− animals (n = 8–9 per group). LV internal diameter at diastole (LVIDd) and at systole (LVIDs) and fractional shortening (FS) are shown in bar graph format. (F) Transcript expression levels of <i>ANP</i> and <i>BNP</i> in control and <i>H-Bmal1</i>^−/− mice at 12 weeks of age (n = 6 per group). (G) Kaplan-Meier survival curves of control and <i>H-Bmal1</i>^−/− animals (n = 31 per group). (H) Low-power views (top panels, scale bar: 1 mm) and high-magnification views (bottom panels, scale bar: 25 µm) of Masson's trichrome staining of heart sections from 33-week-old control and <i>H-Bmal1</i>^−/− mice. (I) High-magnification views of H&E staining of lung (top panels) and liver (bottom panels) sections from the same animals used in (H). Scale bar: 50 µm. Data are the mean ± SEM. *<i>P</i><0.05, **<i>P</i><0.01, unpaired two-tailed Student's <i>t</i>-test.