抗高血压因子对老年心肌梗死血栓形成的抑制作用

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

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 -PGFla)则增加了 80 2 %。AHF对凝血酶诱发的老年人血小板内Ca2 + 浓度的增加值可降低 1 9 3% (均P <0 0 5)。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 -PGFla的比值及抑制血小板Ca2 + 内流 ,从而抑制血小板的聚集有关。

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.