Potassium tolerance and bronchial reactivity in asthmatic and nonasthmatic atopic subjects

Abnormal autonomic nervous system responsiveness may contribute to the pathogenesis of allergic diseases. Therefore, we measured the β-adrenergic systemic (metabolic) responsiveness by means of acute potassium load in 10 normal healthy subjects and in 19 patients with allergic asthma and/or rhinitis. Ten allergic patients showed a greater potassium increment, as in normal subjects, when potassium was infused in the presence of propranolol. There was no difference between asthmatic and rhinitic patients. We then examined the relation between the response to potassium tolerance and the nonspecific, nonpharmacological bronchial reactivity in response to inhalation of ultrasonically nebulized distilled water. Some allergic patients showed bronchial hyper-reactivity, while others did not show a difference compared with the controls; there was no significant difference between asthmatics and rhinitics, and there was no relation between nonspecific bronchial reactivity and potassium load tolerance. These findings suggest that systemic β-adrenergic hyporesponsiveness may be present only in some allergic patients. There is no demonstrable relation among atopic state, nonspecific, nonpharmacological bronchial reactivity, and systemic β-adrenergic hyporesponsiveness.