Acute airway effects of airborne formaldehyde in sensitized and non-sensitized mice housed in a dry or humid environment

作者:Larsen Soren Thor*; Wolkoff Peder; Hammer Maria; Kofoed Sorensen Vivi; Clausen Per Axel; Nielsen Gunnar Damgard
来源:Toxicology and Applied Pharmacology, 2013, 268(3): 294-299.
DOI:10.1016/j.taap.2013.02.006

摘要

We investigated the role of air humidity and allergic sensitization on the acute airway response to inhaled formaldehyde (FA) vapor. Mice were sensitized to the immunogen ovalbumin (OVA) by three intraperitoneal injections followed by two aerosol challenges, giving rise to allergic airway inflammation. Control mice were sham sensitized by saline injections and challenged by saline aerosols. Once sensitized, the mice were housed at high (85-89%) or low (<10%) relative humidity, respectively for 48 h prior to a 60-min exposure to either 0.4, 1.8 or about 5 ppm FA Before, during and after exposure, breathing parameters were monitored. These included the specific markers of nose and lung irritations as well as the expiratory flow rate, the latter being a marker of airflow limitation. The sensory irritation response in the upper airways was not affected by allergic inflammation or changes in humidity. At high relative humidity, the OVA-sensitized mice had a decreased expiratory airflow rate compared to the saline control mice after exposure to approximately 5 ppm FA. This is in accordance with the observations that asthmatics are more sensitive than non-asthmatics to higher concentrations of airway irritants including FA. In the dry environment, the opposite trend was seen; here, the saline control mice had a significantly decreased expiratory airflow rate compared to OVA-sensitized mice when exposed to 1.8 and 4 ppm FA. We speculate that increased mucus production in the OVA-sensitized mice has increased the "scrubber effect" in the nose, consequently protecting the conducting and lower airways.

  • 出版日期2013-5-1