【摘要】 对比研究了克山病病区和非病区居民的硒状态、血栓素（TXA₂）水平以及血小板聚集性形态,并观察了补硒的影响。发现:（1）血硒水平低的病区居民血小板GSH-Px活性也低;血浆TXA₂、血小板TXA₂生成和聚集性均显著高于非病区;血小板形态有异常,出现变形和团聚血小板。（2）给病区居民补硒（亚硒酸钠,200μgSe/d）12周后,红细胞硒和GSH-Px活性显著增高,血浆TXA₂、血小板TXA₂生成和聚集性均显著低于未补硒居民,但血浆前列环素和β-血小板球蛋白（βTG）、血小板βTG含量和释放率无显著变化;补硒可明显减轻病区居民血小板的形态改变。提示,病区低硒居民血小板的高活化反应是克山病发病的一个危险因素;补硒预防克山病发病的机理之一,在于缓解病区人体血小板的高反应性,从而消除心肌围血管病变发生的基础。更多还原

【Abstract】 Selenium status, platelet thromboxane A2 (TXA2)formation ,aggregation and morphology were comparatively investigated of residents from Keshan disease endemic and non-endemic areas, and the effects of selenium supplementation were also evaluated. The results showed that :①Selenium contents and glutathione peroxidase(GSH-Px)activities in whole blood and erythrocyte and platelet GSH-Px activities were significant lower,and plasma TXA2,arachidonic acidinduced platelet aggregation and TXA2 formation were remarkably higher of residents in the endemic area than in the non-endemic area; ultrastructurally, platelets of low-selenium residents showed signs of abnormalities as proved by the appearance of shape-changed and aggregated platelets. ② Selenium supplementation(200 μg Se/d,as sodium selenite for 12 wk)resulted in significant increases in erythrocyte selenium levels and GSH-Px activities of the residents in the endemic area; plasma TXA2, ADP-induced platelet TXA2 formation and aggregation,as well as thrombin-in-duced platelet aggregation were significantly lower in the supplemented group than in the unsup-plemented residents;no significant differences were observed in plasma PGI2 and βTG,platelet βTG and thrombin-induced platelet PTG release between the two groups;selenium supplementation could moderate the morphological changes in platelets of residents from the endemic area. These data suggest that the platelets of residents in the Keshan disease area appear to be in an activated status, which might be a potential risk factor in the pathogenesis of the disease, and that one of the mechanisms for the preventive effect of selenium supplementation on the incidence of the disease might lie in alleviating the higher platelet activation of residents in the endemic area,thus eliminating the basis for the occurrence of the perivascular necroses in myocardium.更多还原