大脑中动脉狭窄致血小板活化及其与动脉粥样硬化性脑梗死关系

Effect of Middle Cerebral Artery Stenosis on Activated Platelets and Relation with Atherosclerotic Cerebral Infarction

目的:探讨大脑中动脉(MCA)狭窄致血小板活化机制及其与动脉粥样硬化性脑梗死的关系。方法:采用超高磁场(3.0T)MRA和流式细胞仪分别测定78例脑梗死患者大脑中动脉和周围血血小板表面糖蛋白CD62_p、Ⅱ_b-Ⅲ_a表达,并与45例非脑梗死头晕患者对比。结果:78例脑梗死患者见MCA狭窄71例(91.03%),其中轻度MCA狭窄24例,中度MCA狭窄27例,高度MCA狭窄20例;其相应CD62p、Ⅱ_b-Ⅲ_a表达阳性率分别达(4.07±2.99)%、(1.33±0.64)%:(4.96±4.54)%、(2.20±0.87)%和(6.01±4.34)%、(2.31±1.06)%,高度MCA狭窄者活化血小板明显高于正常者和轻度狭窄者(P<0.05)。结论:MCA动脉狭窄引起血管剪切力重构,导致血小板活化,是动脉粥样硬化性脑梗死血栓形成的重要机制。

Aim： To study the effect of middle cerebral artery （MCA）stenosis on activated platelets and the relationship between the effect and atherosclerotic cerebral infarction. Methods ： 3.0T MRA was used to assess MCA stenosis and flow cytometr-y was employed to detect CD62p and GP Ⅱb- Ⅲa expression on circulating platelet in 78 patients with atherosclerotic cerebral infarction and 45 controls. Results ： 71subjects with MCA stenosis were found in 78 patients with atherosclerotic cerebral infarction, among them there were 24 subjects with slight MCA stenosis and 27 moderate stenosis and 20 severe stenosis .The positive percentages of CD62p and Ⅱb-Ⅲa were（4.07 ± 2.99）%, （1.33 ± 0.64）%, respectively in subjects with slight MCA stenosis and were （4.96 ± 4.54）%, （2.20 ± 0.87）%, respectively in subjects with moderate stenosis and were （6.01 ± 4.34）%, （2.31 ± 1.06）%, respectively in subjects with severe stenosis. CD62p and Ⅱb-Ⅲa expression on platelet were significantly higher in patients with severe MCA stenosis than those in normal controls and slight MCA stenosis （P 〈 0.05）. Conclusion ： Platelet activation resulted from wall shear stress of MCA stenosis and was an important pathogenesis of a thrombosis of therosclerotic cerebral infarction.