LAUSR

Objectives: Diet-induced obesity is associated with general lesions characterized by microvascular disease and heart disease characterized by left ventricular hypertrophy and diastolic dysfunction. We exerted the model of high fat and sugar-diet rat(HFHSs) to observe effects of losartan on myocardial remodeling and coronary artery tension in diet-induced obesity. Methods: Twenty adult male Wista rats were fed a normal diet or a diet of HFHS with placebo or losartan simultaneously for eight weeks. And then echocardiography and hemodynamics were performed to evaluate cardiac function, HE saining and Masson trichrome staining to assess the myocardial remolding and coronary microvascular rings to observe changes of vascular tension. Results: 1. Compared with normal diet-fed rats, HFHS diet-fed rats developed an increased left ventricular hypertrophy, EDV (end-systolic volume) and ESV (end-diastolic volume), meanwhile a decrease of left ventricular diastolic function. Treatment with losartan attenuated these changes. There was no significance difference in systolic function between these groups. 2. HE staining showed that the myocardial diameter increased in HFHS group compared with normal diet rats (12.960.50 mm vs. 10.970.27 mm; P < 0.05). Masson trichrome staining confirmed that myocardial fibrosis of HFHS group increased compared with the normal ones (1.230.09% vs. 3.050.17; P < 0.05). And losatan attenuated these increase (11.560.32 vs.12.960.05 mm; P < 0.05) (3.050.17 vs. 1.750.12%; P < 0.05). 3. Compared with normal diet-fed rats, basal tension of coronary artery induced by KCl60 mM increased in HFHS-fed rats (3.440.70 vs.4.500.67mN; P < 0.05), and treatment with losartan decrease the vascular tension of HFHS group (4.500.67mN vs.3.800.57mN; P < 0.05). Conclusion: Losartan can reverse myocardial remodeling and decrease coronary artery