Gilbert I A, Lenner K A, McFadden E R
Airway Disease Center, University Hospitals, Cleveland, Ohio 44106.
J Appl Physiol (1985). 1988 Jun;64(6):2667-74. doi: 10.1152/jappl.1988.64.6.2667.
To explore the role of catecholamine release in the pathogenesis of exercise-induced asthma, we had seven asthmatic and seven normal subjects undergo three hourly exercise challenges that were matched for inspired air temperature, minute ventilation, and relative work loads. Pulmonary mechanics and plasma epinephrine and norepinephrine were measured before, at end exercise, and serially after each challenge. There were no differences in the pattern of sympathoadrenal response of asthmatic and normal subjects, and both groups released sufficient quantities of epinephrine and norepinephrine into the peripheral circulation to allow these compounds to function as circulating hormones. As the catecholamines rose with repetitive exercise, progressive bronchodilation occurred in the asthmatics at the end of the work load, thus decreasing the apparent magnitude of the obstructive response. In addition to their effects on airway smooth muscle, the alpha-adrenergic actions of both catecholamines may have reduced airway wall hyperemia and edema. These data demonstrate that asthmatics do not have a defect in catecholamine release during exercise and that the physiological expression of exercise-induced asthma can be modulated by the sympathoadrenal epiphenomena that are associated with physical exertion.
为了探究儿茶酚胺释放在运动诱发哮喘发病机制中的作用，我们让7名哮喘患者和7名正常人每小时接受三次运动挑战，这些挑战在吸入空气温度、分钟通气量和相对工作量方面相互匹配。在每次挑战前、运动结束时以及运动后连续测量肺力学以及血浆肾上腺素和去甲肾上腺素。哮喘患者和正常人的交感肾上腺反应模式没有差异，两组都向外周循环释放了足够量的肾上腺素和去甲肾上腺素，使这些化合物能够作为循环激素发挥作用。随着儿茶酚胺随着重复运动而升高，哮喘患者在工作量结束时出现进行性支气管扩张，从而降低了阻塞性反应的明显程度。除了对气道平滑肌的作用外，两种儿茶酚胺的α-肾上腺素能作用可能还减轻了气道壁充血和水肿。这些数据表明，哮喘患者在运动期间儿茶酚胺释放没有缺陷，并且运动诱发哮喘的生理表现可以通过与体力活动相关的交感肾上腺附带现象来调节。
