摘要
目的通过临床对硒制剂的使用观察，从基因表达水平探讨心肌缺血再灌注期间微量元素硒拮抗自由基损伤的分子机理。方法将患有单纯房间隔或室间隔缺损的病人分为对照组（23例）和服硒组（23例），服硒组于心脏手术前口服硒制剂共7天。利用生化、原子吸收、逆转录PCR（RTPCR）、基因测序等技术，对以上两组病人于心肌缺血前和再灌注30分钟时的心肌脂质过氧化产物丙二醛（MDA）含量、谷胱甘肽过氧化物酶（GPX）活性、硒（Se）、钙（Ca2+）、镁（Mg2+）等离子浓度、GPXmRNA表达阳性率及其CDNA核苷酸序列进行测定和组间比较。结果（1）服硒7天未引起服硒组病人于心肌缺血前的血浆和血细胞Se含量明显变化;（2）再灌注后服硒组病人红细胞Se含量明显降低，心肌Se含量明显增加，心肌GPX活性的增加幅度小于对照组（8.5％比37.3％），MDA含量比缺血前有所降低;（3）服硒组无论在缺血前或再灌注后心肌GPXmRNA表达阳性率都比对照组高（缺血前分别为73.9％、39.1％，再灌注后分别为82.6％、60.9％），而对两组心肌cDNA核苷酸测序结果证明均为细胞型谷胱甘肽过氧化物酶1（GPX1）。结论补硒组通过提高心肌缺血再灌注30分钟时心肌的Se含量和GPX1表达水平，发挥拮抗自由基对心肌细胞的脂质过氧化损伤作用。
To investigate the modulate mechanism of selenium (Se) on glutathione peroxidase expression in the myocardium by defending against free radical superoxidizing during myocardial ischemia reperfusion (I/R) period.Methods patients with ASD or VSD were separated into coned (23 patients) and Se (23 patients) groups. Patients in the Se group received 400μg Se supplementation each day for 7 days before heart.surgery.Biochemical techniques, atomic absorption, RT-PCR, cDNA sequence testing were taken to evaluate and compe the changes in myocadial MDA level, GPX activity, GPX mRNA expression, GPX cDNA nucleotide sequence, and Se, Ca and Mg concentrations during I/R. Results In Se group, Se supplementation by oral administration neither changed plasma Se content nor blood cells. At 30 minute of myocardial reperfusion, in Se group, Se content in the myocardium did significantly increase but decreased in RBCs, and the elementary of GPX activity was lower than that in coned. Se group had higher myocardial GPX mBNA expression with a normal nucleotida sequence pre-and post-reperfusion. Conclusion Se supplement, which promotes the myocardial Se content and mainly improves GPX mRNA expression during I/R, can defend against free radical superoxidizing damages to the myocardium.
出处
《中华医学杂志》
CAS
CSCD
北大核心
1999年第10期731-734,共4页
National Medical Journal of China
基金
国家自然科学基金!39270199
北京市自然科学基金!7942013
关键词
心肌缺血
再灌注损伤
硒
自由基损伤
Selenium Reperfusion injury, myocardial Gene expression
