依那普利和洛沙坦对自发性高血压大鼠血管重塑的影响

THE EFFECTS OF ENALAPRIL AND LOSARTAN ON VASCULAR REMODELING IN SPONTANEOUSLY HYPERTENSIVE RATS

目的 :观察自发性高血压大鼠胸主动脉结构的改变 ,以及依那普利和洛沙坦的保护作用。方法 :雄性自发性高血压大鼠自 10周龄始 ,给予依那普利、洛沙坦 ,或二者半剂量合用 6周 ,并以年龄、性别、数量相同的未治疗自发性高血压大鼠和正常对照组作对照。测量收缩压和血管壁胶原含量 ,计算机图像分析血管外膜面积、中膜面积、管腔面积和管壁厚度。结果 :自发性高血压大鼠未治疗组的收缩压、血管壁胶原含量、外膜面积、中膜面积和管壁厚度均显著高于正常对照组 (P <0 .0 0 1) ,自发性高血压大鼠各治疗组上述指标显著低于其对照组 ,血管腔面积在各组之间无显著性差别 (P >0 .0 5 )。结论 :自发性高血压大鼠早期大动脉结构的改变主要是血管壁结构的改变 ,依那普利和洛沙坦可有效地降低血压、改善血管重塑。

Objective: To investigate the structural changes of aorta in spontaneously hypertensive rats (SHR), and the protective role of enalapril and losartan. Methods: We administed angiotensin converting enzyme (ACE) inhibitor (enalapril 20mg.kg-1.d-1), AngII receptor type 1 (AT1) antagonist (losartan 25mg.kg-1.d-1), or their combination at half doses (enalapril 10mg.kg-1.d-1, losartan 12.5mg.kg-1.d-1) to SHR from 10 to 16 weeks of age. Male, age-matched untreated SHR (SHRc) and Wistar-Kyoto (WKY) rats served as controls. Systolic blood pressure (SBP) and vascular collagen contents were determined. Adventitia, media and lumen cross-sectional area, wall thickness of the aorta were assessed with computed video processing. Results: Compared with WKY rats, the SBP, vascular collagen contents, adventitia and media cross-sectional area and wall thickness were significantly increased in SHRc ( P <0.001), which were significantly reduced in treated SHR than in SHRc. There were no different in lumen cross-sectional area between each group ( P >0.05). Conclusions: In early stage of SHR, the major structural changes of aorta are the alternation of the vessel wall. Enalapril and losartan can effectively decreased blood pressure, improve vascular remodeling.