Koch G, Franz I W, Gubba A, Lohmann F W
Acta Med Scand Suppl. 1983;672:55-62. doi: 10.1111/j.0954-6820.1983.tb01614.x.
This paper assesses mechanisms that may contribute to the higher incidence of increased muscle fatigue during exercise and reduced exercise performance as observed with selective compared with non-selective beta-adrenoceptor antagonists. Published data and the results obtained in 8 healthy subjects (mean age 23 years) studied before and after acute beta-adrenoceptor blockade with pindolol (nonselective, 10 mg) and metoprolol (beta 1-receptor selective, 100 mg) suggest that the differences in the cardiovascular and respiratory effects between the 2 types of antagonists are marginal and cannot explain the discrepancies concerning exercise perception and performance. Conversely, basic differences between the 2 types of antagonists were shown in different groups of hypertensive men (mean age 32 years) studied before and after 4 weeks of treatment with pindolol (15 mg), and with metoprolol (200 mg) and acebutolol (cardioselective, 500 mg), by single crossover technique. Whereas lipolysis was similarly inhibited by both selective and non-selective antagonists, hypoglycaemia occurred only under non-selective blockade. It apparently reflects the inhibition of glycogen breakdown; concomitant rises in plasma adrenaline and ACTH probably reflect counter-regulatory mechanisms.
本文评估了与非选择性β-肾上腺素能拮抗剂相比，选择性β-肾上腺素能拮抗剂导致运动期间肌肉疲劳增加和运动表现降低发生率更高的潜在机制。已发表的数据以及对8名健康受试者（平均年龄23岁）在使用吲哚洛尔（非选择性，10 mg）和美托洛尔（β1受体选择性，100 mg）进行急性β-肾上腺素能受体阻断前后的研究结果表明，两种拮抗剂在心血管和呼吸效应方面的差异很小，无法解释在运动感知和表现方面的差异。相反，通过单交叉技术，在对不同组高血压男性（平均年龄32岁）进行研究时发现了两种拮抗剂之间的根本差异，这些男性在分别接受4周的吲哚洛尔（15 mg）、美托洛尔（200 mg）和醋丁洛尔（心脏选择性，500 mg）治疗前后接受了研究。虽然选择性和非选择性拮抗剂均同样抑制脂肪分解，但低血糖仅在非选择性阻断情况下发生。这显然反映了糖原分解的抑制；血浆肾上腺素和促肾上腺皮质激素的同时升高可能反映了反调节机制。
