Blunted sympathoadrenal response to exercise in asthmatic subjects.

Six asthmatic subjects and six matched controls performed a standardized exercise test in which resting and post-exercise blood samples were assayed radioenzymatically for catecholamines. Plasma adrenaline one minute after exercise rose over threefold in the controls whereas in the asthmatic subjects there was no increase. Plasma noradrenaline increased to five times the basal concentration in the controls, but to less than half this level in the asthmatic subjects. These results agree with a recent study (Barnes et al. 1981) and suggest there is a marked abnormality of the sympathoadrenal response to exercise in asthmatic subjects.