Cardioprotective Effect Of Hydrogen Sulfide To Heart Failure Of Rats After Myocaidial Infarction And Its Possible Mechenism

Aims:Heart failure (HF) after myocardial infarction (MI) is a major cause of morbidity and mortality worldwide. Recent studies have shown hydrogen sulfide (H2S) has cardioprotective effects. So the present study aimed to elucidate the potential effects of H2S on HF after MI in rats.Main methods:HF model after MI was made by ligating the left anterior descending coronary artery. HF groups and Sham-operated groups of rats were treated with vehicle, NaHS, or propagylglycine (PAG). Equal volumes of vehicle,56μM·kg-1 NaHS or 37.5 mg·kg-1 PAG, were intraperitoneally injected to rats for 6 weeks after operation. Survival rate, lung weight to body weight ratio and left ventricular hemodynamic parameters were measured. The protein and gene expression of Bcl-2, Bax, caspase-3 and cytochrome c were analysed by Western blotting and reverse transcriptase polymerase chain reaction (RT-PCR). TdT-mediated dUTP nick end labeling (TUNEL) and electron microscopy (EM) were used to examine apoptosis of heart tissues.Key findings:NaHS was found to improve the survival rate and lower lung weight to body weight ratio. It increased the left ventricular systolic pressure and the maximum rate of pressure and decreased left ventricular end-diastolic pressure. Furthermore, NaHS promoted Bcl-2 protein and mRNA expression and demoted Bax, caspase-3 protein and mRNA expression in HF rats. We also showed NaHS decreased the leakage of cytochrome c protein from mitochondria to cytoplasm. Histological observation by TUNEL and EM proved that, NaHS inhibited cardiac apoptosis in HF hearts and improved mitochondrial derangements but that PAG aggrevated those indexes.Significance:H2S improved the survival rate and ventricular dysfunction in heart failure rats by inhibiting cardiac apoptosis.