Abstract

Authors had intratracheally installated asbestos fiber to albino rats and observed alveolar lining layers with ruthenium red stain. The results were as follows. 1) On the third day after installation of chrysotile asbestos, ruthenium red positive material on surface of type II pneumocytes was decreased in amount. On the fifth day that of type I pneumocytes was also decreased. On the seventh day ruthenium red positive material was significantly decreased in both type I and type II pneumocytes. Degeneration of osmiophilic inclusion body appeared on the fifth day and later it more pronounced. 2) From the above results, positivity of ruthenium red stain is parallel with degree of type II pneumocyte degradation. So the amount of ruthenium red positive material is closely depended upon functional activity of cells producing ruthenium red positive material.