Animals ; Humans ; Ischemic Preconditioning, Myocardial ; methods ; Myocardial Ischemia ; complications ; therapy ; Myocardial Reperfusion ; methods ; Myocardial Reperfusion Injury ; etiology ; prevention & control

Animals ; Humans ; Ischemic Preconditioning, Myocardial ; MicroRNAs ; Myocardial Ischemia ; genetics ; prevention & control

Humans ; Medicine, Chinese Traditional ; Myocardial Ischemia ; prevention & control ; therapy ; Neovascularization, Pathologic ; prevention & control ; therapy

The aim of this study was to determine if the potassium aspartate and magnesium (PAM) prevent reperfusion-induced ventricular arrhythmias (RIVA) in ischemia-reperfusion (IR) rabbit heart. Thirty rabbits were randomly divided into control, ischemia and PAM groups. Arterially-perfused rabbit left ventricular preparations were made, and transmural ECG as well as action potentials from both endocardium and epicardium were simultaneously recorded in the whole process of all experiments. In control group rabbit ventricular wedge preparations were continuously perfused with Tyrode's solution, and in ischemia group and PAM groups the perfusion of Tyrode's solution was stopped for 30 min. Then the ischemia group was reperfused with Tyrode's solution and the PAM group with Tyrode's solution containing 2.42 mg/L PAM, respectively. ECG, QT interval, transmural repolarization dispersion (TDR) and action potentials from epicardium and endocardium were simultaneously recorded, and the RIVA of the wedge preparation was observed. Compared with control group, TDR and incidence of RIVA were significantly increased in ischemia group (P<0.05). The incidence of RIVA in control, ischemia and PAM group was 0/10, 9/10 and 1/10, respectively. Compared with ischemia group, TDR and incidence of RIVA were significantly reduced in PAM group (P<0.05). Potassium aspartate and magnesium significantly reduce TDR and prevent ventricular arrhythmia in ischemic rabbit heart.
Arrhythmias, Cardiac/etiology ; Arrhythmias, Cardiac/*prevention & control ; Myocardial Ischemia/*complications ; Myocardial Ischemia/physiopathology ; Myocardial Reperfusion Injury/*complications ; Potassium Magnesium Aspartate/*therapeutic use ; Random Allocation

OBJECTIVETo investigate whether adiponectin plays a role in the protection of myocardium in the rat myocardial ischemia preconditioning (IPC) model.

METHODInfarct size was measured by Masson's Trichrome staining, the expression of protein and mRNA of adiponectin at 0, 6, 12 and 24 h after IPC was examined by immunohistochemistry and quantitative real time RT-PCR, plasma levels of adiponectin at above mentioned four time points after IPC were detected by ELISA in IPC and MI rats.

RESULTInfarct size was smaller in IPC than in MI rats (20% ± 2% vs. 31% ± 3%, P < 0.05). The expression of adiponectin mRNA at 6 h and 12 h after IPC was 2.2 and 2.1 times higher than in Sham rats at respective time points (P < 0.05). Immunohistochemistry staining evidenced increased adiponectin expression in the ischemic area and weak expression of adiponectin in non-ischemic area (P < 0.05). Compared to the sham group, the plasma level of adiponectin increased significantly at 0, 6 and 12 h after IPC (0 h: 7.40 ± 0.47 vs. 10.90 ± 1.74; 6 h: 8.18 ± 1.41 vs. 10.98 ± 1.74; 12 h: 6.97 ± 1.02 vs. 9.31 ± 0.96, P < 0.05).

CONCLUSIONIPC reduced infarction size, upregulated the myocardial expression of adiponectin at mRNA and protein levels, and increased plasma adiponectin concentration, suggesting that the adiponectin may play a critical role in the protective effect of IPC.

Adiponectin ; metabolism ; Animals ; Ischemic Preconditioning, Myocardial ; Male ; Myocardial Infarction ; metabolism ; prevention & control ; Myocardial Ischemia ; metabolism ; prevention & control ; Myocardium ; metabolism ; Rats ; Rats, Sprague-Dawley

Animals ; Drugs, Chinese Herbal ; administration & dosage ; therapeutic use ; Ischemic Preconditioning, Myocardial ; methods ; Male ; Myocardial Ischemia ; prevention & control ; Myocardial Reperfusion Injury ; prevention & control ; Rabbits

To explore the protective effects of right coronary artery ischemic preconditioning and post-conditioning on myocardial ischemia reperfusion injury in rabbit heart.
 Methods: A total of 30 rabbits were randomly divided into 4 groups: a control group (n=7), an ischemia reperfusion group (IR group, n=8), an ischemic preconditioning group (IPC group, n=8) and an ischemic post-conditioning group (IPO group, n=7). Venous blood samples were taken at pre-operation, 1 and 6 h post-operation, and the concentration of serum creatine kinase isoenzyme (CK-MB) and cardiac troponin-T (cTn-T) were measured. The infarct area of cardiac muscle was calculated.
 Results: Compared with the IR group, the levels of CK-MB and cTn-T at 1 and 6 h post-operation in the IPC group and the IPO group were reduced (all P<0.05). Compared with the IR group, the infarct size in the IPC group and the IPO group was significantly decreased, with significant difference (both P<0.05) .
 Conclusion: Right coronary artery ischemic preconditioning and post-conditioning exert significant protective effects on the myocardial ischemia reperfusion injury in New Zealand rabbits.
Animals ; Coronary Vessels ; Creatine Kinase, MB Form ; blood ; Heart ; Ischemia ; Ischemic Postconditioning ; Ischemic Preconditioning ; Ischemic Preconditioning, Myocardial ; Myocardial Infarction ; etiology ; pathology ; physiopathology ; prevention & control ; Myocardial Ischemia ; complications ; therapy ; Myocardial Reperfusion Injury ; prevention & control ; Myocardium ; Rabbits ; Troponin T ; blood

Burns ; complications ; pathology ; physiopathology ; Humans ; Mitochondria, Heart ; pathology ; Myocardial Ischemia ; etiology ; prevention & control

BACKGROUND: The prediction of the absolute risk of ischemic heart disease (IHD) is commonly based on the risk prediction equations, originated from the Framingham Heart Study. METHOD: Framingham equation model was applied to participants from 2001 Korean National Health and Nutrition Examination Survey (KNHNES) to estimate the 5 year risk of IHD among Koreans ranging from 30 to 74 year-olds. The estimated risks were compared to the incidence and admission rates from two statistical reports among Koreans. Five year admission rate was estimated by the annual report from National Health Insurance Corporation (NHIC). RESULTS: The average ages (standard deviation) were 34.31(27.23) year-old for KNHNES and 48.26(12.87) year-old for Framingham population used in this study. The risk of IHD predicted by the Framingham equation model substantially exceeded the risks actually reported in Korea. Five-year predicted risks by Framingham equation model were 4.86% for men and 1.93% for women; whereas from incidence data in Korea, five-year risks for acute myocardial infarction (AMI) were for 0.47% for men and 0.18% for women. These AMI incidence was similar to the admission rate (0.34 for men and 0.15 for women) estimated by NHIC. Also, 5-year admission rate of IHD were 1.16 for men and 0.78 for women. The magnitude of risk overestimation by Framingham mode is approximately at least 150 to 320%. CONCLUSION: Korean guidelines for the management for high risk group of IHD need to develop and correct for overestimation to avoid inflation of costs in primary prevention.
Aged ; Female ; Heart ; Humans ; Incidence ; Inflation, Economic ; Korea ; Male ; Myocardial Infarction ; Myocardial Ischemia* ; National Health Programs ; Nutrition Surveys ; Primary Prevention

AIMTo investigated the effect of estrogen on global myocardial ischemia/reperfusion (I/R) injury in ovariectomized (Ovx) rats.

METHODSSprague-Dawley rats were randomly repartitioned into three groups including sham-operated(Sham), ovariectomized (Ovx), or ovariectomized and then given 17beta-estradiol (Ovx + E2). Hearts were excised, mounted on the Langendorff. After the initial stabilization period, all of the three group hearts were randomly divided into normal perfusion subgroup (Control) and I/R perfusion subgroups. Control, perfused for 60 min after stabilization. I/R perfusion subgroups divided into 10 min I + 30 min R, 20 min I + 30 min R, 30 min I + 0 min R, 30 min I + 5 min R, 30 min I + 15 min R and 30 min I + 30 min R. And then, every group hearts were isolated into the single cardiomyocyte. The cardiomyocytes basal contraction and isoproterenol(ISO) stimulation contraction were measured. The viability and yield of cardiomyocytes were counted. LDH and CK concentrations in coronary effluent were assayed with assay kit.

RESULTSThe viability and yield of cardiomyocytes were significantly decreased in the conditions of 30 min ischemia followed by different times of reperfusion. The releases of LDH and CK in coronary effluent were significantly increased in the conditions of 30 min ischemia followed by different times of reperfusion. Except the 10 min and 20 min ischemia, the releases of LDH and CK were significantly increased in Ovx during I/R. Ovx + E2 could abate the heart injury through decreasing the releases of LDH and CK. Besides the control and the 10 min I + 30 min R groups, the myocardial basal and ISO stimulation contraction were higher from Ovx than Sham, and the effect was reversed by Ovx + Ez.

CONCLUSIONThe results indicate estrogen plays a cardioprotective role in global myocardial ischemia/reperfusion injury in ovariectomized (Ovx) rats.

Animals ; Estradiol ; pharmacology ; Estrogens ; pharmacology ; Female ; Myocardial Contraction ; physiology ; Myocardial Ischemia ; physiopathology ; Myocardial Reperfusion Injury ; prevention & control ; Myocytes, Cardiac ; metabolism ; physiology ; Ovariectomy ; Random Allocation ; Rats ; Rats, Sprague-Dawley