Vaile J C, Jordan P J, Stallard T J, Littler W A
Department of Cardiovascular Medicine, Queen Elizabeth Hospital, Edgbaston, Birmingham B15 2TH, UK.
J Hum Hypertens. 2000 Mar;14(3):189-94. doi: 10.1038/sj.jhh.1000962.
The objective of this study was to examine the effects of dihydropyridine calcium antagonist therapy on 24-h baroreflex sensitivity. Twenty-three patients with moderate essential hypertension were studied before and during acute (10 patients) and chronic (21 patients) treatment with a dihydropyridine calcium antagonist (nifedipine, nicardipine or felodipine) as monotherapy in a dose titrated to produce a fall in mean cuff pressure of at least 10%. Twenty-four hour unrestricted ambulatory intra-arterial blood pressure (IABP) and heart rate (R-R interval) were monitored. Baroreflex sensitivity (BRS) was assessed throughout the 24-h period by off-line computer analysis of spontaneous variations in IABP and R-R interval. During acute first dose treatment with a calcium antagonist there was a significant fall in blood pressure (BP), increase in heart rate and reduction in BRS. With chronic therapy (6-16 weeks) there was a continued reduction in mean BP of 11% (P < 0.001), but heart rate had returned to control levels and BRS was significantly increased over the 24 h by 14% (P < 0.01). The increase in BRS was evident during both the waking and sleeping periods, but the greatest increase was during sleep (awake 12% P = 0. 02, asleep 28% P = 0.003). In conclusion, although dihydropyridine calcium antagonists acutely cause a reflex tachycardia associated with a reduced BRS, there is no such effect with chronic therapy. BRS was significantly increased after chronic treatment, with exaggeration of the diurnal pattern. Journal of Human Hypertension (2000) 14, 189-194.
本研究的目的是探讨二氢吡啶类钙拮抗剂治疗对24小时压力反射敏感性的影响。对23例中度原发性高血压患者在急性（10例）和慢性（21例）治疗前及治疗期间进行了研究，使用二氢吡啶类钙拮抗剂（硝苯地平、尼卡地平或非洛地平）作为单一疗法，剂量滴定至使平均袖带压下降至少10%。监测24小时无限制动态动脉血压（IABP）和心率（R-R间期）。通过对IABP和R-R间期的自发变化进行离线计算机分析，在整个24小时期间评估压力反射敏感性（BRS）。在钙拮抗剂急性首剂治疗期间，血压（BP）显著下降，心率增加，BRS降低。慢性治疗（6-16周）期间，平均BP持续下降11%（P<0.001），但心率已恢复至对照水平，24小时内BRS显著增加14%（P<0.01）。BRS的增加在清醒和睡眠期间均明显，但最大增加发生在睡眠期间（清醒时增加12%，P=0.02；睡眠时增加28%，P=0.003）。总之，尽管二氢吡啶类钙拮抗剂急性给药会引起与BRS降低相关的反射性心动过速，但慢性治疗则无此效应。慢性治疗后BRS显著增加，且昼夜模式更为明显。《人类高血压杂志》（2000年）14卷，第189 - 194页 。
