Schiffrin E L, Deng L Y
MRC Multidisciplinary Research Group on Hypertension, Clinical Research Institute of Montréal, Hôtel-Dieu de Montréal Hospital, University of Montréal, Quebec, Canada.
J Hypertens. 1996 Oct;14(10):1247-55. doi: 10.1097/00004872-199610000-00014.
To investigate the effects on resistance artery structure and function of monotherapy with the beta-blocker atenolol or the calcium channel antagonist nifedipine in its once a day form or gastrointestinal therapeutic system (GITS).
Twenty well-controlled essential hypertensive patients matched for age, body mass index, duration and severity of hypertension. Normotensive subjects and untreated hypertensives served as the reference groups.
Resistance-size small arteries (standardized lumen diameter 247 +/- 8 microns) were dissected from a gluteal subcutaneous biopsy, and studied both on a wire myograph as pressurized vessels.
The media width:lumen diameter ratio of arteries was 5.37 +/- 0.09% in normotensive subjects, 5.38 +/- 0.18% in patients treated with nifedipine GITS, 6.81 +/- 0.18% in patients treated with atenolol and 7.08 +/- 0.12% in untreated hypertensives (for each of the latter two groups P < 0.001, versus each of the two former groups). The media stress developed in response to noradrenaline and the endothelium-dependent relaxation induced by acetylcholine were significantly smaller in small arteries from untreated or atenolol-treated patients than they were in those from normotensive subjects or nifedipine GITS-treated patients.
Hypertensive patients with well-controlled blood pressures under treatment for more than 1 year with the once-a-day calcium channel antagonist nifedipine GITS exhibit normal structure and function of gluteal subcutaneous small arteries, whereas similar patients with blood pressure equally well controlled by the beta-blocker atenolol present thicker small arteries with abnormal endothelium-dependent relaxation and altered contractility. Whether this finding applies also to other vascular beds, and whether it is associated with a better outcome in relation to morbidity and mortality resulting from elevated blood pressure, remain to be established.
研究β受体阻滞剂阿替洛尔或一日一次剂型或胃肠道治疗系统（GITS）的钙通道拮抗剂硝苯地平单药治疗对阻力动脉结构和功能的影响。
20例血压控制良好的原发性高血压患者，年龄、体重指数、高血压病程和严重程度相匹配。血压正常者和未经治疗的高血压患者作为参照组。
从臀皮下活检中分离出阻力大小的小动脉（标准化管腔直径247±8微米），并在血管张力测定仪上作为加压血管进行研究。
血压正常者动脉的中膜宽度与管腔直径之比为5.37±0.09%，硝苯地平GITS治疗患者为5.38±0.18%，阿替洛尔治疗患者为6.81±0.18%，未经治疗的高血压患者为7.08±0.12%（后两组与前两组相比，P均<0.001）。未治疗或阿替洛尔治疗患者的小动脉对去甲肾上腺素产生的中膜应力以及乙酰胆碱诱导的内皮依赖性舒张明显小于血压正常者或硝苯地平GITS治疗患者的小动脉。
用一日一次的钙通道拮抗剂硝苯地平GITS治疗1年以上且血压控制良好的高血压患者，其臀皮下小动脉结构和功能正常，而用β受体阻滞剂阿替洛尔使血压同样良好控制的类似患者，其小动脉较厚，内皮依赖性舒张异常，收缩性改变。这一发现是否也适用于其他血管床，以及是否与高血压导致的发病率和死亡率方面的更好预后相关，仍有待确定。
