Effects of exposures to various air pollutants on experimental asthma induction, in particular on its late asthmatic response.

Research Project

Project/Area Number	60570253
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	公衆衛生学
Research Institution	Mie University
Principal Investigator	YOSHIDA Katsumi Mie University Medical School, Professor, 医学部, 教授 (20024664)
Co-Investigator(Kenkyū-buntansha)	KITABATAKE Masayoshi Mie University Medical School, Lecturer, 医学部, 講師 (00024688)
Project Period (FY)	1985 – 1986
Project Status	Completed (Fiscal Year 1986)
Budget Amount *help	¥1,600,000 (Direct Cost: ¥1,600,000) Fiscal Year 1986: ¥300,000 (Direct Cost: ¥300,000) Fiscal Year 1985: ¥1,300,000 (Direct Cost: ¥1,300,000)
Keywords	Nitrogen Dioxide / Airway Sensitization / Breathing Curve / Late Asthmatic Response / Air Pollution / 気管支喘息
Research Abstract	On bronchial asthma, it is pointed out that late asthmatic response (LAR) is important and its significance is large, but its adequate identification/experimental procedure has not been developped for the difficulty of objective long-time observation (over 48 hours) on experimental animals' breathing symptoms. In the first step of our project, new procedure of long-time exact observation on breathing symptoms was planned to be developped. Animals (guinea pigs) were fixed in bodyplethsmo-boxes, and each output was amplified, converted to digital data, and stored in hard-disk. Stored data were analized numerically to obtain the following indices of respiratory frequency, ecpiration/ inspiration-ratio (expiratory/inspiratory elongation), breathing curve pattern, power spectrum of breathing curve etc. With this system, effect of nitrogen dioxide on LAR was investigated. By ovo-albumin or candidaextract spray, it was noticed that LAR was elevated siginificantly by exposure to nitrogen dioxide (0.5 ppm X 24 hours X 4 days).