The effects and related mechanism of salvianolate on rats with myocardial ischemia-reperfusion injury

Abstract

Objective: To investigate the effect and related mechanism of salvianolate on myocardial ischemia-reperfusion (I/R) injury in rats. Methods: Thirty-six adult Sprague-Dawley rats were divided into three groups (n=12 each) using random number table method: control group (coronary artery was not ligated) , I/R group (myocardial I/R model was established by ligation and opening of left anterior descending coronary artery) , and salvianolate+I/R group (5 mg/kg of salvianolate was injected through the tail vein at the time of reperfusion) .Triphenyltetrazolium chloride (TTC) stain was utilized to measure the myocardial infarct size. The ELISA method was used to detect myocardial necrotic markers, including cardiac troponin T (TnT) , creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH) . Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was used to analyses the levels of apoptosis. The levels of cleaved Caspase-3 protein were analyzed with Western blot.Cold luminescence method was used to detect the ATP level of myocardial tissue. The levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in myocardial tissue were detected by immunofluorescence. Results: (1) The infarct size in control group, I/R group and salvianolate+I/R group were 0, (23.90±5.66) %, and (12.06±5.97) %, respectively (P<0.01 or 0.05) . (2) The TnT level was (0.04±0.03) , (16.96±2.80) , and (6.95±2.31) ng/ml, the CK-MB level was (43.6±23.5) , (1 135.8±180.6) ,and (390.3±121.5) U/L, the LDH level was (119.0±58.6) , (1 838.6±543.8) , and (631.6±228.3) U/L in control group, I/R group and salvianolate+I/R group, all significantly lower in salvianolate+I/R group than in I/R group (all P<0.01) . (3) The rate of TUNEL positive myocardial cells were (1.07±1.16) %, (21.36±4.11) %,and (13.30±3.67) % in control group, I/R group,and salvianolate+I/R group (all P<0.01) . (4) The cleaved Caspase-3 expression was 0.11±0.05, 0.84±0.20,and 0.43±0.09 in control group, I/R group, and salvianolate+I/R group (all P<0.01) . (5) The ATP level of myocardial tissue was (100.0±0.0) %, (34.2±9.2) %,and (62.1±18.0) % respectively in control group, I/R group, and salvianolate+I/R group (all P<0.01) . (6) There was almost no 8-OHdG expression in the myocardial tissue of control group. The expression of 8-OHdG in the myocardial tissue of I/R group was greater than that of the control group. The expression of 8-OHdG in the myocardial tissue of salvianolate+I/R group was less than that of the I/R group. Conclusion: Salvianolate may alleviate myocardial I/R injury of rat through reducing the mitochondrial DNA oxidative damage, protecting mitochondrial function and inhibiting the apoptosis of myocardial cells.