Reilly C S, Wood M, Koshakji R P, Wood A J
Clin Pharmacol Ther. 1985 Nov;38(5):579-85. doi: 10.1038/clpt.1985.227.
Esmolol is a beta 1-selective adrenoceptor blocker that is rapidly metabolized by blood and liver esterases. The beta-receptor and hemodynamic effects of esmolol were determined in a group of 12 healthy men and were compared with those induced by both oral and intravenous propranolol. Esmolol was rapidly effective in inducing at least 90% of steady-state beta-blockade within 5 minutes of either initiating or changing the esmolol infusion rate. More importantly, when esmolol infusion was discontinued the beta-blockade had totally disappeared by 18 minutes after esmolol, 300 micrograms/kg/min, and had been reduced by 50% after 750 micrograms/kg/min. In contrast, 30 minutes after discontinuation of a propranolol infusion, there was no change in the level of beta-blockade. Propranolol was much more potent at blocking isoproterenol-induced tachycardia (dose ratio 33.5 +/- 2.5) than was even the highest dose (750 micrograms/kg/min) of esmolol (dose ratio 13.1 +/- 1.0). The same dose of intravenous propranolol was approximately equipotent to oral propranolol, 40 mg every 8 hours (dose ratio 33.5 +/- 2.5 and 34.5 +/- 3.6, respectively). In contrast, propranolol, 40 mg every 8 hours, and esmolol, 300 micrograms/kg/min, were equipotent in antagonizing exercise-induced tachycardia (40.1% +/- 2.3% and 42.7% +/- 3.2%, respectively). Esmolol had striking hypotensive effects. Systolic blood pressure fell by 20 mm Hg during esmolol infusions of 750 micrograms/kg/min. Esmolol appears to be a potent beta 1-selective adrenoceptor antagonist with a particularly strong hypotensive effect. It is likely to be very useful in the treatment of hemodynamically unstable patients and may be useful in the emergency treatment of hypertension.
艾司洛尔是一种β1选择性肾上腺素能受体阻滞剂，可被血液和肝脏酯酶迅速代谢。在一组12名健康男性中测定了艾司洛尔的β受体和血流动力学效应，并与口服和静脉注射普萘洛尔所诱导的效应进行了比较。在开始或改变艾司洛尔输注速率后的5分钟内，艾司洛尔能迅速有效地诱导至少90%的稳态β受体阻滞。更重要的是，当停止输注艾司洛尔后，在输注300微克/千克/分钟的艾司洛尔后18分钟时β受体阻滞完全消失，而在输注750微克/千克/分钟后750微克/千克/分钟时β受体阻滞减少了50%。相比之下，在停止普萘洛尔输注30分钟后，β受体阻滞水平没有变化。普萘洛尔在阻断异丙肾上腺素诱发的心动过速方面（剂量比为33.5±2.5）比即使是最高剂量（750微克/千克/分钟）的艾司洛尔（剂量比为13.1±1.0）更有效。相同剂量的静脉注射普萘洛尔与每8小时口服40毫克普萘洛尔大致等效（剂量比分别为33.5±2.5和34.5±3.6）。相比之下，每8小时口服40毫克普萘洛尔和300微克/千克/分钟的艾司洛尔在对抗运动诱发的心动过速方面等效（分别为40.1%±2.3%和42.7%±3.2%）。艾司洛尔有显著的降压作用。在输注750微克/千克/分钟的艾司洛尔期间，收缩压下降了20毫米汞柱。艾司洛尔似乎是一种强效的β1选择性肾上腺素能受体拮抗剂，具有特别强的降压作用。它可能在治疗血流动力学不稳定的患者中非常有用，并且可能在高血压的紧急治疗中有用。
