Smith S R, Kendall M J
Int J Clin Pharmacol Ther Toxicol. 1986 Jan;24(1):1-3.
Beta 2-agonists are known to cause a range of unwanted biochemical and cardiovascular responses. The present study was designed to investigate the effect of chronic exposure to beta 2-stimulation on the magnitude of these responses produced by an acute challenge with a beta 2-agonist. In this single blind placebo controlled study in six healthy male volunteers, we have compared the effects of chronic dosing with either oral terbutaline (5 mg three times daily for two weeks) or placebo on a number of these responses produced by an intravenous infusion of terbutaline (6 micrograms per kilogram over 1 hour). The infusion was given twenty-four hours after the last dose of oral terbutaline or placebo. The rise in pulse rate, systolic blood pressure and plasma glucose and the fall in serum potassium during terbutaline infusion, although still demonstrable, were significantly reduced following treatment with oral terbutaline compared to placebo. This suggests downgrading of beta-receptor function after chronic beta 2-stimulation.
已知β2激动剂会引发一系列不良的生化和心血管反应。本研究旨在调查长期暴露于β2刺激对急性β2激动剂激发所产生的这些反应程度的影响。在这项针对六名健康男性志愿者的单盲安慰剂对照研究中，我们比较了口服特布他林（每日三次，每次5毫克，持续两周）或安慰剂长期给药对静脉输注特布他林（每千克6微克，持续1小时）所产生的一系列反应的影响。静脉输注在最后一剂口服特布他林或安慰剂后24小时进行。与安慰剂相比，口服特布他林治疗后，特布他林输注期间脉搏率、收缩压和血糖的升高以及血清钾的降低虽然仍可显现，但显著减轻。这表明长期β2刺激后β受体功能降低。
