Orehek J, Gayrard P, Grimaud C, Charpin J
J Allergy Clin Immunol. 1975 Mar;55(3):164-9. doi: 10.1016/0091-6749(75)90012-3.
Dose-responses curves were established in 10 normal subjects by measuring, with a body plethysmograph, the changes of specific airway conductance (SGaw) produced by aerosolized acetylcholine. Doses of acetylcholine producing a 50 per cent decrease of control SGaw (ED50) were found to be largely variable among individuals. Beta-adrenergic blockade with intravenous propranolol (0.2 mg per kilogram) resulted in a mean potentiation of the acetycholine effect (mean ED50 after propranolol was significantly lower than mean ED50 before). This potentiating effect of propranolol, however, was also subjected to individual variations, suggesting individual variability of the sympathetic system. The range of variation in acetylcholine sensitivity was not narrowed by propranolol treatment and no correlation was found between initial acetylcholine sensitivity and propranolol potentiation. This suggests that variability of the sympathetic system is not the main factor in determining individual variation in acetylcholine sensitivity. Even when propranolol was very effective in increasing airway sensitivity, this sensitivity was still less marked than usually encountered in asthmatic patients. This suggests that beta-adrenergic blockade cannot create, if alone, the bronchial hypersensitivity characteristic of asthma.
通过体容积描记器测量雾化乙酰胆碱引起的比气道传导率（SGaw）变化，在10名正常受试者中建立剂量反应曲线。发现导致对照SGaw降低50%的乙酰胆碱剂量（ED50）在个体间差异很大。静脉注射普萘洛尔（0.2毫克/千克）进行β肾上腺素能阻滞导致乙酰胆碱效应平均增强（普萘洛尔后的平均ED50显著低于之前的平均ED50）。然而，普萘洛尔的这种增强效应也存在个体差异，提示交感神经系统存在个体变异性。普萘洛尔治疗并未缩小乙酰胆碱敏感性的变异范围，且初始乙酰胆碱敏感性与普萘洛尔增强作用之间未发现相关性。这表明交感神经系统的变异性不是决定乙酰胆碱敏感性个体差异的主要因素。即使普萘洛尔在增加气道敏感性方面非常有效，这种敏感性仍不如哮喘患者通常所见明显。这表明单独的β肾上腺素能阻滞不能产生哮喘特有的支气管高敏反应。
