Effects of estradiol on platelet aggregation in cerebral microvessels of mice.
Effects of estradiol on platelet aggregation in cerebral microvessels of mice.
复制标题
雌二醇对小鼠脑微血管血小板聚集的影响。
作者：
Rosenblum,WI;el-Sabban,F;Allen,AD;Nelson,GH;Bhatnagar,AS;Choi,SC
小鼠皮下植入含有 0.5 mg 雌二醇的颗粒或安慰剂。 8至12天后，通过有害光/染料刺激损伤体内的软脑膜小动脉内皮，从而在软脑膜小动脉中产生血小板聚集。通过对年轻（2个月大）小鼠进行雌二醇治疗，有害刺激发生与血小板聚集出现之间的时间显着缩短（p小于0.02）。相同的治疗对 4-6 个月大的小鼠产生相反的效果，并显着延迟聚集的发生 (p = .01)。当制备富含血小板血浆（PRP）时，无论年龄如何，雌二醇处理的小鼠的 PRP 中花生四烯酸钠的聚集始终受到抑制。雌二醇治疗对 ADP 体外诱导的聚集没有影响。因此，在年轻雌二醇治疗小鼠的软脑膜小动脉中观察到的聚集增强可能并不反映雌二醇对血小板本身的直接作用。这些数据是根据文献进行讨论的，文献表明接受雌激素，特别是高剂量雌激素的患者会加剧缺血性血管疾病，包括中风。
Mice were implanted subcutaneously with a pellet containing 0.5 mg estradiol or with a placebo. Eight to 12 days later platelet aggregation was produced in pial arterioles by injuring their endothelium in vivo with a noxious light/dye stimulus. The time between the onset of the noxious stimulus and the appearance of platelet aggregates was significantly shortened (p less than .02) by estradiol treatment in young (2 month old) mice. The same treatment had the opposite effect in 4-6 month old mice and significantly delayed the onset of aggregation (p = .01). When platelet rich plasma (PRP) was prepared, aggregation by sodium arachidonate was always inhibited in PRP from estradiol treated mice, irrespective of age. Estradiol treatment had no effect on aggregation induced ex vivo by ADP. Thus the enhanced aggregation observed in pial arterioles of young estradiol treated mice may not reflect direct effects of estradiol on the platelet itself. The data are discussed in light of the literature suggesting enhancement of ischemic vascular disease, including strokes, in patients receiving estrogens, and especially high doses of estrogens.