硒对大鼠心肌线粒体NADH-细胞色素C还原酶活性的影响

用克山病病区低硒粮喂养大鼠,动态观察硒对心肌线粒体鱼藤酮不敏感的NADH—细胞色素C还原酶(RINCR)活性的影响。研究结果表明,病区粮喂养30d后心肌硒含量和线粒体谷胱甘肽过氧化物酶(GPX)活性明显下降,补硒可维持心肌硒水平和GPX活性接近常备饲料组大鼠水平或超过之。病区粮喂养30和60d时,心肌线粒体RINCR活性明显降低;至90d时有所恢复,但仍低于补硒和常备饲料组。补硒60和90d时,RINCR活性明显高于病区粮组,于90d时与常备饲料组已无明显差异。结果说明,克山病病区粮喂养大鼠心肌线粒体RINCR活性下降,补硒可部分恢复之,提示病区粮中除低硒外,还可能存在其它致病因素。

THE EFFECT OF SELENIUM ON THE ACTIVITY OF MITOCHONDRIAL NADH-CYTOCHROME C REDUCTASE IN MYOCARDIUM OF RATS

The effect of selenium on the mitochondrialrotenone-insensitive NAPH-cytoehrome C reduc-tase activity was dynamically investigated in my-ocardium of rats fed low--selenium cereals from aKeshan disease area. Cardiac selenium contentsand mitochondrial glutathione peroxidase activitieswere reduced significantly after feeding cerealsfrom the endemic area for 30 d, Se-supplementcould maintain cardiac Se contents and GSH px ac-tivities to the extent approaching or above those ofrats fed stock diets. After feeding cereals from theendemic area for 30～60 d, mitochondrial RINCRactivities in myocardium were decreased signifi-cantly, for 90 d the activities showed recovery tosome extent, but still lower than those of Se-sup-plemented rats and rats fed stock diets. RINCR ac-tivities were remarkably higher in Se-supplementedrats than in rats fed cereals from endemic area af-ter 60 and 90 d of feeding, the activities were com-parable to those of rats fed stock diets for 90 d.The results indicated that the mitochondrial RIN-CR activities in myocardium were inhibited whenrats were fed with the cereals from the Keshan dis-ease area, and Se-supplements could partially alle-viate this inhibition, suggesting that other patho-genetic factor (s) besides Se-deficiency might bepresented in the cereals from the endemic area.