Fang Z Y, Li Y F, Zhang L L, Liu D J, Li Y Q
Shanxi Cardiovascular Institute, Taiyuan, China.
Zhongguo Yao Li Xue Bao. 1996 Nov;17(6):519-23.
To study the effect of the angiotensin-converting enzyme (ACE) inhibitors perindopril (Per) and enalaprilat (Ena) on the reactivity of the endothelium in normal rats.
Male rats were treated intragastrically with Per (2 mg.kg-1.d-1) or placebo (n = 18) for 6 wk. Aorta was isolated for experiment. Another set of isolated aortic rings with and without endothelium were incubated with Ena (0.1 mumol.L-1) for 30 min. Responses to acetylcholine, serotonin, phenylephrine, sodium nitroprusside (SN), and nitroglycerin (Nit) were observed.
Endothelium-dependent relaxation to acetylcholine was augmented in aortic rings from rats treated with Per in comparison with control. The IC50 value (95% confidence limits) decreased from 3.8 (0.56-26.1) mumol.L-1 (control group) to 0.98 (0.28-3.41) mumol.L-1 (Per-treated group). The maximal relaxation was augmented from 62 +/- 9% to 78 +/- 10% (P < 0.01). However, the responses to the endothelium-independent vasodilators, SN and Nit, were similar. Serotonin- and phenylephrine-induced contractions were decreased, which were influenced by basal release of endothelium-derived relaxing factor (EDRF). EC50 values was 6.1 (2.6-14.4) nmol.L-1 vs 8.3 (3.6-18.8) nmol.L-1 in comparison with control group and Per-treated group. The maximal contraction was decreased from 2.42 +/- 0.29 g (control group) to 1.96 +/- 0.25 g (treated group) (P < 0.01). Similar results were found in incubation with Ena.
Ena and Per enhanced the basic release of EDRF from vascular endothelium.
研究血管紧张素转换酶（ACE）抑制剂培哚普利（Per）和依那普利拉（Ena）对正常大鼠血管内皮反应性的影响。
雄性大鼠经胃给予Per（2mg·kg⁻¹·d⁻¹）或安慰剂（n = 18），持续6周。分离主动脉进行实验。另一组有内皮和无内皮的离体主动脉环与Ena（0.1μmol·L⁻¹）孵育30分钟。观察对乙酰胆碱、5-羟色胺、去氧肾上腺素、硝普钠（SN）和硝酸甘油（Nit）的反应。
与对照组相比，用Per治疗的大鼠主动脉环中对乙酰胆碱的内皮依赖性舒张增强。IC50值（95%置信限）从3.8（0.56 - 26.1）μmol·L⁻¹（对照组）降至0.98（0.28 - 3.41）μmol·L⁻¹（Per治疗组）。最大舒张从62±9%增加到78±10%（P < 0.01）。然而，对非内皮依赖性血管舒张剂SN和Nit的反应相似。5-羟色胺和去氧肾上腺素诱导的收缩减弱，这受到内皮源性舒张因子（EDRF）基础释放的影响。与对照组和Per治疗组相比，EC50值分别为6.1（2.6 - 14.4）nmol·L⁻¹和8.3（3.6 - 18.8）nmol·L⁻¹。最大收缩从2.42±0.29g（对照组）降至1.96±0.25g（治疗组）（P < 0.01）。在与Ena孵育时发现了类似结果。
Ena和Per增强了血管内皮中EDRF的基础释放。
