Reid J L, Millar J A, Campbell B C
J Hypertens Suppl. 1983 Oct;1(1):129-34.
Enalapril (10 mg), in young sodium replete normotensive males significantly reduced systolic and diastolic blood pressures in both the supine and erect posture without orthostatic effects. As with captopril (25 mg) erect and supine heart rate did not differ from that after inactive placebo even at the time of maximum blood pressure reduction. The absence of reflex bradycardia was not related to a sympatho-inhibitory effect as the responses to Valsalva's manoeuvre, cold stress and dynamic and isometric exercise were unchanged by enalapril. Plasma noradrenaline was not different from that found after placebo treatment. Increased parasympathetic tone may contribute to the absence of tachycardia after converting enzyme inhibitors.
依那普利（10毫克），在钠储备充足的年轻血压正常男性中，显著降低了仰卧位和直立位的收缩压和舒张压，且无体位性影响。与卡托普利（25毫克）一样，即使在血压最大降幅时，直立位和仰卧位的心率与服用无活性安慰剂后相比也没有差异。无反射性心动过缓与交感神经抑制作用无关，因为依那普利对瓦尔萨尔瓦动作、冷应激以及动态和等长运动的反应未发生改变。血浆去甲肾上腺素与安慰剂治疗后无差异。副交感神经张力增加可能是转换酶抑制剂后无心动过速的原因之一。
