Comparative effects of SCH 1000 and fenoterol after histamine-induced bronchoconstriction in asymptomatic asthmatics.

In 16 asymptomatic asthmatics a functional study was carried out under controlled conditions during histamine bronchial provocation test (HBPT) and after bronchodilation test with either SCH 1000 or fenoterol by evaluating both SRAW and the slope of the alveolar plateau of nitrogen washout curve (N2 ph III). During HBPT, 9 of 16 subjects showed a central response (increase in RAW and SRAW only), whereas in the remaining 7 subjects histamine induced a mixed response due to an increase in both SRAW and N2 ph III. No differences between the two groups were observed in age and functional data during controlled conditions. Doses of delivered histamine were not significantly different. In 5 of 9 central responders to HBPT, SCH 1000 induced a decrease in SRAW only, whereas in 3 of the remaining 4 fenoterol caused both central and peripheral bronchodilation (decrease in both SRAW and N2 ph III). All mixed responders to HBPT showed a mixed bronchodilation during SCH 1000 (three subjects) or fenoterol (the remaining four). These data seem to indicate that the mechanism of bronchodilation induced by SCH 1000 is related to that of histamine-induced bronchoconstriction. Moreover, bronchodilation due to fenoterol could be related to a vagal modulation or be a systemic direct effect.

Effects of steroid therapy on pulmonary involvement in sarcoidosis.

In eleven patients with stage II-III pulmonary sarcoidosis as assessed by mediastinoscopy or open lung biopsy, we carried out a functional study by evaluating static and dynamic pulmonary volumes, diffusing lung properties (TLCO, KCO), and mechanical properties: resistance of the airway, flow-volume curve, pressure-volume curve, flow-pressure curve, and dynamic compliance. In 7 of 11 patients a clinical and functional follow-up during steroid treatment over a period of 5 months to 3 years was also performed. Before treatment diffusing properties were in the normal range in 6 of 11 subjects, reduced in 4, and increased in 1. Elastic properties studied in 8 patients were in the normal range, whereas peripheral airway involvement was noted in 4 nonsmokers. During the follow-up the changes noted in diffusing lung properties on the whole parallelled the clinical and radiologic improvement or relapses after cessation of therapy. In contrast, no changes in elastic properties or lung volume were noted. We concluded that steroid treatment seems to improve parenchymal lung involvement in most cases as shown by the increase in diffusing lung properties.