Abstract
The lung histamine contents of air-control and O3-, SO2-, NO2- exposed guinea pigs were compared, and the water content of the lungs was estimated in each group. It was noted that the mean histamine content of the lungs of animals exposed to low and high concentrations of ozone was below the mean of the control group. Lung edema was produced by both low and high concentrations of ozone exposure. Massive lung edema was also produced in the lungs of guinea pigs exposed to a high concentration of NO2, while there was no significant change in the mean histamine content of the lungs. Using an apparatus for perfusion of isolated lungs of guinea pigs, a large amount of histamine was found to be contained in the perfusion out-flow collected during 0 to 90 minutes from O3-ventilated lungs.