阿斯匹林精氨酸对兔缺血心肌不应期和室颤阈变化的影响

实验观察了阿斯匹林精氨酸(AAs)对兔缺血心室肌不应期(ERP)和室颤阈(VFT)的影响。结果表明,阻断冠脉50min时,血小板聚集率(PAgR)增大11±5%,VFT降低24±3mA;缺血边缘区ERP较缺血10 min时缩短20±10 ms,缺血中心区延长35±12 ms,两区间不应期离散性(Di)增加52±17ms,各数值均与对照值差异显著(p<0.01)。阻断冠脉前0.5 hⅳAAs,上述参数变化明显减轻,与单纯阻断组缺血50 min时各数值变化相比,均p<0.01。结果提示,AAs具有抑制PAgR、减小Di和提高VFT的作用。

EFFECTS OF ARGININE ASPIRIN ON CHANGES IN EFFECTIVE REFRACTORY PERIOD AND VENTRICULAR FIBRILLATION THRESHOLD OF ISCHEMIC MYOCARDIUM IN RABBIT

The effects of arginine aspirin (AAs) on the effective refractory period (ERP) and ventricular fibrillation threshold (VFT) of ischemic ventricular muscle were observed in 24 anesthetized open-chest rabbits. that the platelet aggregation rate was shown to be increased by 11 +/- 5%, and VFT decreased by 24 +/- 3 mA at 50 min after coronary occlusion. Compared with values at 10 min postocclusion, ERP of ventricular muscle in border ischemic zone (BIZ) and central ischemic zone (CIZ) was shortened by 20 +/- 10% and prolonged by 35 +/- 22 ms, respectively, and dispersions of ERP between CIZ and BIZ were increased by 52 +/- 17 ms, compared with control values, (p less than 0.01). By giving an intravenous injection of AAs at 0.5 h before coronary occlusion, changes in parameters as mentioned above were obviously relieved as compared with the same parameters in the group of simple coronary occlusion at 50 min postocclusion, (p less than 0.01). These results suggest that AAs may inhibit platelet aggregation, reduce dispersions of ERP and elevate VFT after coronary occlusion.