Pritchard J N, Holmes A, Evans J C, Evans N, Evans R J, Morgan A
Environ Res. 1985 Apr;36(2):268-97. doi: 10.1016/0013-9351(85)90025-8.
A comparison was made of the distribution of dust in the rat lung following its administration by inhalation and by a single intratracheal instillation. Due to the wide variety of instillation techniques, an "average" method was adopted based on the results from a survey of 15 laboratories in Europe and the USA. Novel techniques were developed to quantify the distribution of dust within the lung both microscopically and macroscopically. The distribution of dust obtained by instillation was shown to be much less homogeneous that that obtained by inhalation and penetration to the periphery was minimal. The effects of (a) changing the volume of suspension, (b) changing the concentration of the suspension, and (c) introducing air into the syringe were investigated. Although the use of air in the syringe was beneficial, none of the other modifications effected any improvement in the distribution. The difference in distribution following inhalation and instillation leads to the conclusion that the latter may be of use in establishing the nature and comparative response of the lung to different dusts, but not for establishing an absolute dose-response relationship. It is recommended that no more than 1 mg of fibrous or 5 mg of nonfibrous dust be given in a single instillation to adult rats.
对大鼠经吸入和单次气管内滴注给予粉尘后肺内粉尘分布情况进行了比较。由于滴注技术种类繁多，基于对欧洲和美国15个实验室的调查结果采用了一种“平均”方法。开发了新技术以在微观和宏观层面量化肺内粉尘的分布。结果显示，通过滴注获得的粉尘分布远不如通过吸入获得的均匀，且向周边的渗透极少。研究了（a）改变悬浮液体积、（b）改变悬浮液浓度以及（c）向注射器中注入空气的影响。尽管在注射器中使用空气有益，但其他任何改变均未使分布得到改善。吸入和滴注后分布的差异得出结论：滴注法可用于确定肺对不同粉尘的性质和比较反应，但不适用于建立绝对剂量反应关系。建议对成年大鼠单次滴注给予的纤维性粉尘不超过1毫克，非纤维性粉尘不超过5毫克。
