MacGregor G A, Rotellar C, Markandu N D, Smith S J, Sagnella G A
J Cardiovasc Pharmacol. 1982;4 Suppl 3:S358-62.
Nifedipine was given to 15 patients with essential hypertension for 6 weeks and to 8 normotensive subjects for 5 days. In the hypertensives, 30 min after the first dose of nifedipine (5-mg capsule), there was a 13.9% fall in mean blood pressure (p less than 0.001), and, at the 6th week of treatment at the maximum dose of 20 mg t.d.s., a 20.6% fall in mean blood pressure (p less than 0.001). In the normotensive subjects, 30 min after the first dose of 5 mg of nifedipine, there was a 2.3% fall in mean blood pressure (NS), and on the 5th day with the maximum dose of 20 mg t.d.s., the fall was 2.2% (NS). In view of the difference in age between these normotensive and hypertensive subjects, a larger group of patients with essential hypertension and older normotensive subjects were also studied acutely after a single 5-mg capsule of nifedipine. Thirty minutes after the first dose of nifedipine in the larger group of hypertensives, there was a significant fall in mean blood pressure (10.4%; p less than 0.001, n = 33). In the normotensive subjects, there was also a significant fall in mean blood pressure (4.7%; p less than 0.01, n = 29). This was significantly less than in the hypertensives (p less than 0.001). In both the normotensive and hypertensive subjects, there was a significant correlation between pretreatment blood pressure and percentage decrease in blood pressure with nifedipine. Nifedipine, therefore, has a greater blood pressure-lowering effect the higher the initial blood pressure. This finding is compatible with the idea that nifedipine reveals a functional abnormality of vascular smooth muscle that becomes greater the higher the blood pressure.
对15例原发性高血压患者给予硝苯地平治疗6周，对8例血压正常者给予硝苯地平治疗5天。在高血压患者中，首次服用硝苯地平（5毫克胶囊）30分钟后，平均血压下降13.9%（p<0.001）；在治疗第6周，最大剂量为每日3次、每次20毫克时，平均血压下降20.6%（p<0.001）。在血压正常者中，首次服用5毫克硝苯地平30分钟后，平均血压下降2.3%（无统计学意义）；在第5天，最大剂量为每日3次、每次20毫克时，血压下降2.2%（无统计学意义）。鉴于这些血压正常者和高血压患者之间存在年龄差异，还对一大组原发性高血压患者和年龄较大的血压正常者在单次服用5毫克硝苯地平胶囊后进行了急性研究。在较大组的高血压患者中，首次服用硝苯地平30分钟后，平均血压显著下降（10.4%；p<0.001，n=33）。在血压正常者中，平均血压也显著下降（4.7%；p<0.01，n=29）。这明显低于高血压患者（p<0.001）。在血压正常者和高血压患者中，治疗前血压与硝苯地平治疗后血压下降百分比之间均存在显著相关性。因此，初始血压越高，硝苯地平的降压效果越大。这一发现与硝苯地平揭示血管平滑肌功能异常且血压越高异常越明显的观点相符。
