Enhanced pulmonary inflammatory response to ozone during lactation in rats: evaluation of the influence of inhaled dose.
Weideman PA; Chen LC; Gunnison AF
Inhal Toxicol 1996 Jul; 8(5):495-519
The influence of inhaled dose on the pulmonary inflammatory response to ozone (10028156) in lactating rats was investigated. Groups of lactating and postlactating Sprague-Dawley-rats were exposed either to filtered air or to nominal ozone concentrations of 0.3, 0.5 or 1.0 part per million (ppm) for 6 hours. Lactating rats were exposed on day 13 postpartum. Postlactating rats were exposed on day 13 postpartum, 10 days after pups were removed. Ventilation was measured during ozone exposure using barometric plethysmography. In response to increased metabolic demand, the minute volume of air breathing in postpartum rats on day 13 of lactation increased to about 150% of that of age matched post lactating rats with the same lung size. This resulted in greater inhaled ozone doses in lactating rats compared to postlactating rats identically exposed. The authors conclude that these findings confirm earlier reports of enhanced pulmonary inflammation in lactating rats compared to postlactating rats following exposure to these concentrations of ozone. A significant portion, but not all, of this enhanced response can be accounted for by the greater ventilation of lactating rats compared to postlactating rats, which results in a greater inhaled dose of ozone at equivalent atmospheric concentrations.
NIOSH-Publication; NIOSH-Grant; Training; Laboratory-animals; Toxic-gases; Lung-irritants; Pollutants; Respiratory-system-disorders; Pulmonary-function; Reproductive-effects
Community Medicine Mount Sinai School of Medicine One Gustave L Levy Place Bx108 New York, NY 10029
Mount Sinai School of Medicine, New York, New York