Olmesartan restores the protective effect of remote ischemic perconditioning against myocardial ischemia/reperfusion injury in spontaneously hypertensive rats.

OBJECTIVES: Remote ischemic perconditioning is the newest technique used to lessen ischemia/reperfusion injury. However, its effect in hypertensive animals has not been investigated. This study aimed to examine the effect of remote ischemic perconditioning in spontaneously hypertensive rats and determine whether chronic treatment with Olmesartan could influence the effect of remote ischemic perconditioning. METHODS: Sixty rats were randomly divided into six groups: vehicle-sham, vehicle-ischemia/reperfusion injury, vehicle-remote ischemic perconditioning, olmesartan-sham, olmesartan-ischemia/reperfusion and olmesartan-remote ischemic perconditioning. The left ventricular mass index, creatine kinase concentration, infarct size, arrhythmia scores, HIF-1α mRNA expression, miR-21 expression and miR-210 expression were measured. RESULTS: Olmesartan significantly reduced the left ventricular mass index, decreased the creatine kinase concentration, limited the infarct size and reduced the arrhythmia score. The infarct size, creatine kinase concentration and arrhythmia score during reperfusion were similar for the vehicle-ischemia/reperfusion group and vehicle-remote ischemic perconditioning group. However, these values were significantly decreased in the olmesartan-remote ischemic perconditioning group compared to the olmesartan-ischemia/reperfusion injury group. HIF-1α, miR-21 and miR-210 expression were markedly down-regulated in the Olmesartan-sham group compared to the vehicle-sham group and significantly up-regulated in the olmesartan-remote ischemic perconditioning group compared to the olmesartan-ischemia/reperfusion injury group. CONCLUSION: The results indicate that (1) the protective effect of remote ischemic perconditioning is lost in vehicle-treated rats and that chronic treatment with Olmesartan restores the protective effect of remote ischemic perconditioning; (2) chronic treatment with Olmesartan down-regulates HIF-1α, miR-21 and miR-210 expression and reduces hypertrophy, thereby limiting ischemia/reperfusion injury; and (3) recovery of the protective effect of remote ischemic perconditioning is related to the up-regulation of HIF-1α, miR-21 and miR-210 expression.

Protective effect of olmesartan against cardiac ischemia/reperfusion injury in spontaneously hypertensive rats.

Olmesartan, as a new angiotensin II receptor blocker, has shown beneficial effects on cardiovascular diseases. Nevertheless, the effect of olmesartan on ischemia/reperfusion (I/R) injury in the hypertensive heart has not been investigated. Therefore, the present study aimed to investigate the effect of olmesartan on I/R injury in spontaneously hypertensive rats (SHRs). Experimental groups were designed with a 2×2 factorial design for olmesartan and I/R effects. In the I/R group, the left anterior descending coronary artery (LAD) was ligated for 40 min followed by a 180-min reperfusion. In the sham group, SHRs underwent the same surgical procedure as the I/R group, with the exception that the suture passed under the LAD without being tightened. In the Olm-I/R group, the SHRs received olmesartan (5 mg/kg) for 4 weeks prior to surgery and other procedures were the same as for the I/R group. In the Olm-sham group, the SHRs received olmesartan (5 mg/kg) for 4 weeks prior to surgery and other procedures were the same as for the sham group. Infarct size was measured for the I/R and Olm-I/R groups. Blood pressure (BP), serum creatine kinase (CK), left ventricular mass index (LVMI), high mobility group box 1 (HMGB1) protein expression levels and hypoxia-inducible factor-1α (HIF-1α) mRNA expression levels were measured for all four groups. Olmesartan significantly reduced BP and LVMI in the olmesartan-treated SHRs compared with those in the SHRs that were not treated with olmesartan. HMGB1 and HIF-1α expression levels were significantly decreased in the Olm-sham and Olm-I/R groups compared with those in the sham and I/R groups, respectively. The proportional increase in HIF-1α expression due to I/R was greater in the olmesartan-treated rats than in the untreated rats. Serum CK levels were significantly reduced in the Olm-I/R group compared with those in the I/R group. In conclusion, olmesartan ameliorates left ventricular hypotrophy and protects the heart against I/R injury in addition to lowing BP in SHRs. The protective effect of olmesartan may be partly due to its antioxidative and anti-inflammatory properties.

Olmesartan restores the protective effect of remote ischemic perconditioning against myocardial ischemia/reperfusion injury in spontaneously hypertensive rats

OBJECTIVES: Remote ischemic perconditioning is the newest technique used to lessen ischemia/reperfusion injury. However, its effect in hypertensive animals has not been investigated. This study aimed to examine the effect of remote ischemic perconditioning in spontaneously hypertensive rats and determine whether chronic treatment with Olmesartan could influence the effect of remote ischemic perconditioning. METHODS: Sixty rats were randomly divided into six groups: vehicle-sham, vehicle-ischemia/reperfusion injury, vehicle-remote ischemic perconditioning, olmesartan-sham, olmesartan-ischemia/reperfusion and olmesartan-remote ischemic perconditioning. The left ventricular mass index, creatine kinase concentration, infarct size, arrhythmia scores, HIF-1α mRNA expression, miR-21 expression and miR-210 expression were measured. RESULTS: Olmesartan significantly reduced the left ventricular mass index, decreased the creatine kinase concentration, limited the infarct size and reduced the arrhythmia score. The infarct size, creatine kinase concentration and arrhythmia score during reperfusion were similar for the vehicle-ischemia/reperfusion group and vehicle-remote ischemic perconditioning group. However, these values were significantly decreased in the olmesartan-remote ischemic perconditioning group compared to the olmesartan-ischemia/reperfusion injury group. HIF-1α, miR-21 and miR-210 expression were markedly down-regulated in the Olmesartan-sham group compared to the vehicle-sham group and significantly up-regulated in the olmesartan-remote ischemic perconditioning group compared to the olmesartan-ischemia/reperfusion injury group. CONCLUSION: The results indicate that (1) the protective effect of remote ischemic perconditioning is lost in vehicle-treated rats and that chronic treatment with Olmesartan restores the protective effect of remote ischemic perconditioning; (2) chronic treatment with Olmesartan down-regulates HIF-1α, ...

[Prevalence of coronary artery disease in patients with rheumatic heart disease in China].

OBJECTIVE: To investigate the prevalence of coronary artery disease (CAD) and the atherosclerotic risk factors in the patients undergoing valvular surgery due to rheumatic heart disease. METHODS: Consecutive 651 patients with rheumatic heart disease aged > 40 who were scheduled for valve surgery underwent diagnostic coronary angiography to delineate coronary arteries. Significant coronary artery disease was considered to be present if one or more single coronary branches showed 50% or more luminal stenosis. Symptoms, such chest pain, were evaluated. Established risk factors for CAD, such as diabetes mellitus, systemic hypertension, smoking, and dyslipidemia were evaluated. Previous history of myocardial infarction and coronary artery bypass surgery was also recorded. RESULTS: Seventy-one patients (10.91%), 54 males and 17 females, were detected as with CAD. The mean age of the patients with CAD was (63 +/- 9), significantly higher than that of the patients with normal coronary arteries [(54 +/- 9), P < 0.01]. The atheromatous lesion mostly involved the left descending branch (38.12%), and 38 patients (53.52%) showed lesions in 2 or more branches. The prevalence rates of diabetes mellitus and hypertension in the CAD group were 32.39% and 29.58% respectively, both significantly higher than those in the non-CAD group (7.41% and 19.48% respectively; P < 0.01 and P = 0.047). The smoking rate of the CAD group was 36.62%, significantly higher than that of the non-CAD group (12.93%; P < 0.01). However, there were not significant differences in the prevalence rates of dyslipidemia and ECG ST-T changes between these 2 groups (both P > 0.05). No relation was found between the rheumatic disease and coronary disease distribution (P > 0.05). CONCLUSION: Coronary angiography should be performed in all patients clinically suspected with CAD, aged > 50 and the patients with angina and/or coronary risk factors in order to decrease the occurrence of operative complications.