Time course of maximum expiratory flow volume (MEPV) curves in the Wistar rat after acute ozone exposure
Tijdverloop van de maximale expiratoire flow volume (MEPV) curven in de wistar rat na acute blootstelling aan ozon
Boere AJF, Marra M, Rombout PJA
RIVM Report 619002004
Acute exposure of humans to ambient ozone levels resulted in decreased lung function and inflammation of the respiratory system. The time-course of the inflammation measured in clinical studies and in laboratory animal studies are in agreement. The time-course of lung function changes in laboratory animals has been investigated in this study. Effects on lung function due to acute ozone exposure are maximal immediately after exposure. During the Maximal Expiratory Flow Volume (MEFV) curves increased forced expiratory flow (FEF) were measured both 0, 6, and 12 hours post exposure. Effects are abolished within 24 hours post exposure. In contrast to effects of ozone exposure on lung function parameters measured in clinical studies, increased FEF's are found in the Wistar rat exposed for 12 hour to 1.6 mg/m3 ozone. This opposite effect could be caused by the method of measuring lung function in laboratory animals. The animals are anaesthetized and the maximal in- and expiration must be forced by external pressure.