Figure 1: Preliminary Study Using Echocardiography, Biomarker Measurement, and Radiotelemetry

(A) Correlation curve for serum troponin I level and fractional shortening obtained from 18 mice 1 day after myocardial infarction (MI), with a correlation coefficient of −0.710 (p = 0.001). (B, C) At 1 day after MI, fractional shortening in infarcted mice was significantly lower, and the serum troponin I level in infarcted mice was significantly higher, compared with sham-operated mice (p < 0.05 and p < 0.05, respectively). There were no differences in these parameters between MI mice treated with vehicle, enalapril, and LCZ696. Results were mean ± SD. n = 5 to 6 per group. ∗p < 0.05 vs. sham. (D) 24-h average SBP in mice treated with enalapril and LCZ696. Each drug was administered in an incremental manner every week by gastric gavage once daily. The dose of 20 mg/kg BW/day LCZ696 and 4 mg/kg BW/day enalapril were the maximum that did not lower baseline blood pressure. Results were mean ± SD. n = 4 per group. (E) Circadian rhythm of SBP in mice treated with LCZ696. There were no differences among 20 mg/kg BW/day LCZ696, 4 mg/kg BW/day enalapril, and baseline during the 12-h dark and 12-h light periods. There was no interaction between group and period (p = 0.182 for interaction). Results were mean ± SD. BW = body weight; POD = post-operative day; SBP = systolic blood pressure.