Bur S, Bachofen H, Gehr P, Weibel E R
Exp Lung Res. 1985;9(1-2):57-66. doi: 10.3109/01902148509061528.
Instillation of glutaraldehyde into the airways of collapsed lungs is a widely used fixation procedure for analysis of pulmonary structure-function relations. In order to better define the effect of this fixation method on the pulmonary microvasculature, a morphometric analysis was made in rat lungs fixed under different conditions. In one group of animals the lungs were allowed to collapse; then the circulation was suddenly interrupted with a sling placed in the coronary sulcus before instillation of the fixative. In a second group the same procedure was carried out with the exception that the lungs were kept inflated at the time of circulatory arrest. In third group the standard technique was used, i.e., the collapsed lungs were instilled before circulatory arrest. The results show that important parameters of alveolar and septal dimensions, and in particular the capillary surfaces and volumes, are alike regardless of the procedure of fixation. However, in lungs fixed by the standard technique a higher capillary hematocrit (approximately 33%) and a decreased harmonic mean thickness of the plasma barrier were found. This artificial hemoconcentration in the microvasculature resulted in a substantial morphometric overestimate of the diffusing capacity of the lung.
将戊二醛滴注到萎陷肺的气道中是一种广泛用于分析肺结构 - 功能关系的固定方法。为了更好地确定这种固定方法对肺微血管系统的影响，对在不同条件下固定的大鼠肺进行了形态计量分析。在一组动物中，让肺萎陷；然后在滴注固定剂之前，用置于冠状沟的吊带突然中断循环。在第二组中，除了在循环停止时肺保持膨胀外，进行相同的操作。在第三组中使用标准技术，即在循环停止前对萎陷的肺进行滴注。结果表明，无论固定程序如何，肺泡和间隔尺寸的重要参数，特别是毛细血管表面积和体积都是相似的。然而，在用标准技术固定的肺中，发现毛细血管血细胞比容较高（约33%），血浆屏障的调和平均厚度减小。微血管系统中的这种人为血液浓缩导致对肺扩散能力的形态计量学高估。
