Distribution of injury and microdosimetry of ozone in the ventilatory unit of the rat.
Distribution of injury and microdosimetry of ozone in the ventilatory unit of the rat.
复制标题
大鼠呼吸机损伤分布和臭氧微剂量测定。
DOI：
10.1152/jappl.1992.73.3.817
复制
发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Crapo,JD
中科院分区：
文献类型：
--
作者：
Pinkerton,KE;Mercer,RR;Plopper,CG;Crapo,JD
臭氧引起的肺损伤的分布在整个呼吸单位进行了测定，并与相同单位的臭氧剂量的预测分布进行了比较，以评估剂量-反应关系。Sprague-Dawley大鼠暴露于0.98 ppm臭氧8小时/天，持续90天，或仅暴露于过滤空气。采用整块显微切割法在纵断面上识别和分离细支气管肺泡管连接处、第一对肺泡管生成处和介入分叉脊。沿每个分离的细支气管壁沿着的第一个肺泡外袋被用于识别一系列同心弧的中心，这些同心弧以100微米的间隔向外辐射穿过每个呼吸单元。测量每个弧与肺泡隔尖端（边缘）和肺泡壁组织的截距长度，并表示为进入呼吸单位的距离的函数。使用气管支气管树的几何形状以及单个呼吸机单元内的体积和表面积分布来估计呼吸机单元的相对臭氧剂量。这种臭氧剂量的数学模型显示出与所测量的组织损伤反应的高度相关性。本研究的结果表明，微剂量学和微毒理学可用于确定剂量反应关系内的消毒单位，并评估臭氧引起的肺损伤的组织敏感性的问题。
The distribution of ozone-induced injury across ventilatory units of the lungs was determined and compared with the predicted distribution of ozone dose across the same units to evaluate dose-response relationships. Sprague-Dawley rats were exposed to either 0.98 ppm ozone 8 h/day for 90 days or to filtered air only. En bloc microdissection was used to identify and isolate in longitudinal profile the bronchiole-alveolar duct junction, first pair of alveolar duct generations, and intervening bifurcation ridge. The first alveolar outpocketing along the bronchiolar wall of each isolation was used to identify the center of a series of concentric arcs radiating outward at 100-microns intervals across each ventilatory unit. The intercept lengths of each arc with the tissue of alveolar septal tips (edges) and alveolar walls were measured and expressed as a function of distance into the ventilatory unit. Relative ozone dose across the ventilatory unit was estimated using the geometry of the tracheobronchial tree and the volume and surface area distribution within individual ventilatory units. This mathematical model of ozone dose demonstrated a high degree of correlation to this measured tissue injury response. The findings of this study demonstrate that microdosimetry and microtoxicology can be used to determine dose-response relationships within the ventilatory unit and to assess questions of tissue sensitivity in ozone-induced lung injury.