Gleerup G, Mehlsen J, Winther K
Department of Clinical Physiology, Fredericksberg Hospital, Denmark.
J Cardiovasc Pharmacol. 1995 Jan;25(1):87-9. doi: 10.1097/00005344-199501000-00014.
The effects of isradipine and atenolol on platelet function and fibrinolytic activity were studied in 10 male patients with mild untreated hypertension. After a 2-week placebo run-in period, the volunteers were randomized to either isradipine 2.5 mg twice daily or atenolol 100 mg daily for a 6-month period. Those initially receiving isradipine then received atenolol and vice versa. After each therapy regimen, blood was drawn at rest and 1 h after exercise during a maximum exercise test. Platelet activity in vivo was estimated as release of B-TG and PF-4. Fibrinolytic activity was estimated as the fast-acting inhibitor against tissue plasminogen activator usually termed PAI-1. During atenolol and isradipine therapy, blood pressure (BP) was equally reduced (p < 0.05). Heart rate (HR) decreased during atenolol treatment but was not changed by isradipine. Platelet activity in vivo estimated as B-TG and PF-4 decreased irrespective of therapy (p < 0.02). During atenolol, as during placebo therapy, exercise resulted in a significant increase in platelet activity, as shown by an increase in B-TG (p < 0.02) and in PF-4 (p < 0.01). Such increase was not observed during isradipine treatment. Both treatments tended to improve fibrinolysis, as shown by a decrease in PAI, 1 h after exercise. Reducing BP with isradipine or atenolol results in a similar decrease in platelet activity and PAI-level, tested at rest and 1 h after rest, respectively. During exercise, platelet activity increased during atenolol treatment; such change did not occur during isradipine treatment.
在10名未经治疗的轻度高血压男性患者中研究了伊拉地平与阿替洛尔对血小板功能和纤溶活性的影响。经过2周的安慰剂导入期后，志愿者被随机分为两组，一组每天服用2次2.5mg伊拉地平，另一组每天服用100mg阿替洛尔，为期6个月。最初接受伊拉地平治疗的患者随后接受阿替洛尔治疗，反之亦然。在每种治疗方案结束后，在最大运动试验期间静息时和运动后1小时采血。体内血小板活性通过β-血小板球蛋白（B-TG）和血小板第4因子（PF-4）的释放来评估。纤溶活性通过通常称为纤溶酶原激活物抑制剂-1（PAI-1）的对组织纤溶酶原激活物的快速作用抑制剂来评估。在阿替洛尔和伊拉地平治疗期间，血压（BP）均有同等程度降低（p<0.05）。阿替洛尔治疗期间心率（HR）下降，但伊拉地平对心率无影响。无论采用何种治疗，以B-TG和PF-4评估的体内血小板活性均下降（p<0.02）。在阿替洛尔治疗期间，与安慰剂治疗期间一样，运动导致血小板活性显著增加，表现为B-TG增加（p<0.02）和PF-4增加（p<0.01）。在伊拉地平治疗期间未观察到这种增加。两种治疗均倾向于改善纤溶，表现为运动后1小时PAI下降。分别在静息时和静息后1小时测试，伊拉地平或阿替洛尔降低血压会导致血小板活性和PAI水平出现类似下降。运动期间，阿替洛尔治疗时血小板活性增加；伊拉地平治疗时未出现这种变化。
