妊娠高血压与先兆子痫可能与血栓素A_2(TXA_2)的生成过多有关,TXA_2由胎盘和血小板产生,有较强的收缩血管和促使血小板凝聚的作用。每日服用1～2mg/公斤体重的小剂量阿司匹林可有效地抑制血小板的环氧化酶和血小板合成TXA_2。作者对无并发症的初孕妇在妊娠26周时,静脉滴往血管紧张素Ⅱ,在用量≤10ng/公斤/分能有效地引起舒张压上升 Pregnancy-induced hypertension and preeclampsia may be related to the excessive production of TXA_2. TXA_2 is produced by the placenta and platelets, which has strong effects of contracting blood vessels and promoting platelet aggregation. A small dose of aspirin administered daily at 1 to 2 mg / kg body weight effectively inhibits TXA 2 synthesis by platelet cyclooxygenase and platelets. The authors of early complications of pregnant women at 26 weeks of gestation, intravenous infusion of angiotensin Ⅱ, in the dose of ≤ 10ng / kg / min can effectively cause an increase in diastolic blood pressure