2002 年 51 巻 5 号 p. 505-508
To determine the effects of high temperature on the number of alveolar macrophages (AMs) in bronchoalveolar lavage (BAL) fluid in rats, F344 rats were housed in environment chambers at 23°C, 30°C or 35°C for up to 14 days. The number of AMs in the BAL fluid was significantly decreased in rats housed at 35°C on days 7 and 14, compared to the control group housed at 23°C. The total protein content and lactate dehydrogenase activity did not change at high temperatures in BAL supernatant, indicating that there was no increase in alveolar/capillary barrier permeability or lung cellular injury. The results might suggest that high temperature (35°C) affects the pulmonary defense mechanism.