Endogenous glucocorticoids and antigen‐induced acute and late phase pulmonary responses

BACKGROUND: Several studies suggest that endogenous glucocorticoids can dampen the severity of experimental allergic reactions in animals. OBJECTIVE: To investigate the influence that endogenous glucocorticoids have on the course of IgE-mediated pulmonary early and late phase reactions. METHODS: Twenty-one allergic asthmatic and six healthy control subjects underwent inhaled antigen challenge with measurements of plasma cortisol and cortisone by gas chromatography-mass spectrometry. RESULTS: There were no differences between the asthmatic and control groups in the baseline levels of cortisol or cortisone. However, the asthmatic subjects had significantly higher cortisol levels (67.2 +/- 8.6 vs 35.1 +/- 4.5 ng/mL; P = 0.04) and had higher cortisol/cortisone ratios (4.8 +/- 0. 6 vs 3.0 +/- 0.2; P = 0.01) 8 h after challenge compared to the control subjects. Among the asthmatic subjects, those whose FEV1 recovered rapidly had higher baseline levels of cortisol and those who displayed a late phase reaction had lower levels of cortisol during the late phase period. CONCLUSION: The results suggest that endogenous glucocorticoids may play a significant role in the modulation of airway responses to antigen challenge, and that antigen challenge may induce cortisol production in allergic subjects.