Stiles J, Tyler W S
Department of Anatomy, School of Veterinary Medicine, University of California, Davis 95616.
Toxicol Appl Pharmacol. 1988 Feb;92(2):274-85. doi: 10.1016/0041-008x(88)90387-0.
The influence of age on morphologic changes in lungs of rats exposed to ozone was studied in female Sprague-Dawley rats, aged 60 and 444 days. Rats of both age groups were exposed continuously for 72 hr to either 0.35 or 0.80 ppm ozone, or to filtered air. Tissues were evaluated using light microscopic morphometry and scanning electron microscopy. The lungs from ozone-exposed 60-day-old rats had larger volume fractions of centriacinar lesions than lungs from exposed 444-day-old rats. Within each age group there was an observed dose response, with rats exposed to 0.80 ppm ozone having larger volume fractions of lesions than those exposed to 0.35 ppm. Only the 444-day-old rats lost body weight during the exposure period. They also had smaller fixed lung volumes than same-aged controls. All 60-day-old rats gained weight during the exposure period, although rats exposed to 0.80 ppm ozone gained less than filtered air controls. Lesions observed in both age groups of female rats were qualitatively similar to those previously described in young adult male rats. We conclude that there are age-related differences in the morphometric responses of rats to ozone exposure. Younger rats had larger proportions of centriacinar lesions and macrophages while older rats had greater body weight and lung volume changes.
在60日龄和444日龄的雌性斯普拉格-道利大鼠中，研究了年龄对暴露于臭氧的大鼠肺部形态变化的影响。两个年龄组的大鼠连续72小时暴露于0.35 ppm或0.80 ppm的臭氧中，或暴露于过滤空气中。使用光学显微镜形态测量法和扫描电子显微镜对组织进行评估。与暴露于臭氧的444日龄大鼠的肺相比，暴露于臭氧的60日龄大鼠的肺中叶中心性腺泡病变的体积分数更大。在每个年龄组中都观察到了剂量反应，暴露于0.80 ppm臭氧的大鼠的病变体积分数大于暴露于0.35 ppm的大鼠。只有444日龄的大鼠在暴露期间体重减轻。它们的固定肺体积也比同龄对照组小。所有60日龄的大鼠在暴露期间体重增加，尽管暴露于0.80 ppm臭氧的大鼠比过滤空气对照组增加得少。在两个年龄组的雌性大鼠中观察到的病变在性质上与先前在年轻成年雄性大鼠中描述的病变相似。我们得出结论，大鼠对臭氧暴露的形态测量反应存在与年龄相关的差异。年轻大鼠的叶中心性腺泡病变和巨噬细胞比例更大，而老年大鼠的体重和肺体积变化更大。
