Airway response to salbutamol: effect of regular salbutamol inhalations in normal, atopic, and asthmatic subjects.
AUTOR(ES)
Harvey, J E
RESUMO
This study was designed to determine whether resistance to the airway effects of the beta-agonist, salbutamol, would develop in three groups of subjects while taking large doses of inhaled salbutamol. Six normal non-atopic, six atopic non-asthmatic, and eight atopic asthmatic subjects were studied by an identical technique. The development of resistance was assessed from salbutamol dose-response studies in which the airway response was measured as specific airway conductance (sGaw). Further evidence was sought in the atopic and asthmatic subjects by measuring the airway response to a standard histamine inhalation challenge and the protective effect of 100 micrograms salbutamol on this challenge, and by six-hourly peak flow recordings. Subjects were assessed before and during four weeks in which they took inhaled salbutamol regularly in doses increasing to 500 microgram quid in week 4. Normal subjects showed a progressive reduction in the bronchodilator (sGaw) response to salbutamol during the four weeks, indicating the progressive development of resistance. The atopic subjects, both asthmatic and non-asthmatic, showed no reduction in the response to salbutamol during the four weeks, nor any change in the response to histamine challenge or in regular peak flow readings. These results demonstrate that asthmatic patients do not develop bronchial beta-adrenoceptor resistance easily and suggests that they and atopic non-asthmatic subjects are less susceptible to its development than normal subjects.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=459298Documentos Relacionados
- Cytokine expression in normal, atopic, and asthmatic subjects using the combination of sputum induction and the polymerase chain reaction.
- Effect of prior bronchoconstriction on the airway response to histamine in normal subjects.
- Effect of bronchodilators on the cough response to inhaled citric acid in normal and asthmatic subjects.
- Effect of nedocromil sodium on the airway response to inhaled capsaicin in normal subjects.
- The nasal response to exercise and exercise induced bronchoconstriction in normal and asthmatic subjects.