[Mechanism of selenium protecting against free radical damages during myocardial ischemia/reperfusion in rats].
摘要
OBJECTIVE: To investigate the mechanism of selenium (Se) protecting against free radical damages during myocardial ischemia/reperfusion (I/R) in rats. METHODS: All rats were separated into three groups: control, organic Se and inorganic Se supplemented groups. Myocardial I/R was established by operation in all three groups. Biochemical assays, atomic absorption spectrophotometry, RT-PCR and cDNA sequence scanning were performed to examine the changes in myocardial MDA level, GSH-Px activity and gene expression, GSH-Px cDNA nucleotide sequence, as well as Se and Ca2+ and Mg2+ concentrations in the heart muscle during I/R. RESULTS: The administration of Se for 7 days did not significantly change the content of Se in the plasma and blood cells. In the two Se-supplemented groups, after reperfusion for 30 minutes, myocardial Se concentration and GSH-Px activity were increased significantly, and GSH-Px expression was elevated with a normal cDNA sequence, and at the same time, MDA contents in the two Se-supplemented groups were lower than that in the control group. CONCLUSION: Se supplementation can protect against free radical damages during myocardial I/R by increasing myocardial Se content and improving both the expression and activity of GSH-Px.