Histopathological studies on experimentally induced pulmonary adenomatosis in guinea-pig lungs.

The main purpose of our experimental series was to induce, in experimental animals, diffuse pulmonary fibrosis resembling that in human lungs. In the lungs of guinea-pigs injected with a soluble immune complex and continuously exposed to a 40-60 per cent oxygen-rich atmosphere, diffuse pulmonary fibrosis occurred in many cases in the course of 2 to 3 months after the injection. After the 100th experimental day, multiple foci of pulmonary adenomatosis occurred. The morphology was similar to that of Jaagsiekte. Electron microscopic observations revealed that these hyperplastic cells originated from type II pneumoncytes.