ABSTRACT
In 35 guinea pigs a model of pneumonia was produced by transtracheal introduction of a sterile string. Electron microscopic study revealed that in the early stage of pneumonia (3-14 days after onset) endothelial cells in the capillaries of alveolar walls develop changes aimed at intensification of their function in sustaining an enhanced transcapillary gas exchange. In the following stage (1-4 months) endothelial cells develop progressing dystrophic changes leading to structural and functional disturbance of the blood-oxygen barrier. The dystrophic changes in endothelial cells develop later than those in alveolar epithelium.
Subject(s)
Endothelium, Vascular/ultrastructure , Lung/blood supply , Pneumonia/pathology , Animals , Capillaries/physiopathology , Capillaries/ultrastructure , Endothelium, Vascular/physiopathology , Female , Guinea Pigs , Male , Pneumonia/physiopathologyABSTRACT
The study of changes of ultrastructure of air-blood-barrier components in comparison with indices of surfactant surface activity was carried out on fragments of lung tissue, cut from 36 patients with bronchiectasis, chronic abscess and fibrosis of post-pneumonic nature. Our data indicate, that in patients with chronic non-specific lung diseases the areas, more distant from the focus of affection, have changes, involving all the components of air-blood-barrier. Dystrophic and destructive processes, taking place in some pneumocytes of the 2nd type, result in suppression of the surface active characteristics of surfactant. On the other hand, processes of compensatory nature, directed to making up a deficiency of surfactant, take place.
