抗高血压因子对老年心肌梗死血栓形成的抑制作用

目的 探讨抗高血压因子（AHF）在老年心肌梗死时对血栓形成的抑制作用及机制。方法 以老龄大鼠心肌梗死模型,腹腔注射AHF加以保护。结果 AHF保护组较非保护组心肌内血栓数量降低了53．8％,心肌内钙含量降低37．1％,血浆中血栓素B2（TXB2）降低45．6％和血小板聚集率（PAg)降低了50．5％;前列环素（6－Keto-PGF1a)则增加了80．2％。AHF对凝血酶诱发的老年人血小板内Ca^2 浓度的增加值可降低19．3％（均P＜0．05）。结论 AHF在老年心肌梗死时对血栓形成具有明显抑制作用,其机制与AHF防止心肌细胞钙超载、降低血浆TXB2／6－Keto-PGF1a的比值及抑制血小板Ca^2 内流,从而抑制血小板的聚集有关。

Inhibitory effects of antihypertensive factor on thrombosis followed myocardial infarction in the elderly

Objective To study the inhibitory action and mechanism of antihypertensive factor(AHF) on thrombosis followed myocardial infarction in the elderly.Methods Model of isoproterenal (ISO)-induced myocardial infarction in old Wistar rats (ISO 60 mg/kg, sc)was used. AHF (4 mg/kg)was injected intraperitoneally.Results In the AHF protected group, the number of thrombus, calcium content in cardiac muscle, plasma thromboxane B 2 (TXB 2) and platelet aggregation were significantly reduced by 53.8%, 37 1%, 45.6% and 50.5% compared to control group( P<0.05 ).Level of 6-Keto-PGF la increased by 80.2% ( P<0.05 ). Utilizing Fura-2 fluorescence indicator, AHF reduced 19.3% of the elevated of Ca 2+ concentration in platelet induced by thrombin in normal elderly ( P<0.05 ).Conclusion AHF may suppress thrombosis followed myocardial infarction in the elderly, related to the reduced calcium overload of myocardial cells and inhibition of platelet.