Protective effect of 1-(2,6-dimethylphenoxy)-2-(3,4-dimethoxyphenylethylamino) propane hydrochloride on myocardial ischemia-reperfusion injury in rats

The aim of the present study was to investigate the protective effect of 1-(2,6-dimethylphenoxy)-2-(3,4-dimethoxyphenylethylamino) propane hydrochloride (DDPH) on myocardial ischemia-reperfusion (I/R) injury in rats and the mechanism of its myocardial protection. For this purpose, 50 Wistar rats were divided into five groups: sham group, control group, verapamil treated group, and two DDPH treated groups (20 and 40 mg/kg, respectively). Myocardial I/R injury model was established by reperfusion for 120 min after 40 min ischemia induced by the ligation of left descending coronary artery in rats. The influence of DDPH on myocardial infarction size was observed and the levels of myocardial enzymes in serum were measured. The activities of oxygen free radical scavenging enzymes and the content of malondialdehyde (MDA) in myocardium and serum were determined. The pathological changes of myocardial tissue were observed. The results showed that DDPH significantly diminished myocardial infarction size, reduced the release of myocardial creatine phosphokinase (CPK), lactate dehydrogenase (LDH) and glutamic oxaloacetic aminotransferase (GOT), protected the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and decreased the content of MDA in myocardium and serum as compared with the control group. The degree of myocardial injury was slighter in DDPH treated groups than in control group. These results suggest that DDPH produces a cardioprotective effect during myocardial I/R injury, which may be related to blocking calcium channels and inhibiting the formation of the oxygen free radical and subsequent peroxidation of lipid by DDPH.