Abstract
We measured time related changes of lung functions, plasma substance P, histamine and leucotriene C4 (LTC4) in 18 asthmatic patients and 5 normal subjects following inhalation of ultrasonically nebulized distilled water (USNDWI) and of isotonic (0.9 %) saline to clarify the mechanism of bronchial response after USNDWI. None of the subjects investigated had obvious changes in pulmonary functions due to the isotonic saline. However, while normal subjects had no apparent change after USNDWI, among the asthmatic patients, 9 had an immediate bronchial response (JAR alone group), 5 had immediate and late bronchial responses (dual AR group), and 4 had no brochial response (nonresponder group) . In the dual AR group, plasma substance P tended to increase in JAR and LAR, and plasma histamine and LTC4 tended to increase in JAR. The results suggest that the mechanism of JAR after USNDWI may be due to provocation of a chemical mediator release from mast cells through axonal reflex, and that the development of LAR itself after USNDWI revealed relations between these mechanisms and mast cells.
