Ultrastructural changes in the non-cardiogenic pulmonary oedema.

The report has been divided in two parts. In the first part, the authors review the chief features of the alveolar-capillary membrane permeability. In the second part, are described the early ultrastructural changes observed in the sheep lung, three and twenty-four hours after the haemorragic shock indication. At third hour, the lesions showed a very heterogeneous distributive pattern. The interstitial oedema was the most striking feature at this time, but some important morphological lesions within endothelial and epithelial layers could be also observed. A large amount of neutrophyls on the way to degranulation or already degranulated were observed in the interstitium especially in the most damaged areas. The morphological status of the junctional complex was normal. After twenty-four hours, typical hyaline membranes and areas of well developed alveolar oedema could be seen.