Lung alterations in newborn rabbits after maternal thrombin-shock. I. Morphological alterations

Alterations of the lung structure, especially of the pneumocytes type II, of asphyxied newborn rabbits were investigated. Experiments were carried out on pregnant does shocked by thrombin- and Pamba-applications on the 28th, 29th and 30th day of gestation and on their newborns delivered by caesarian section at these days and killed after one or five hours life-time. Histologically, adult rabbits show characteristic alterations in an early phase of the shock. Lung alterations are the main findings in the newborns. Atelectases and, additionally, disturbances of circulation, permeability and also hyaline thrombi are seen. Lamellar bodies within the pneumocytes type II show a significant decrease of the lamellae and the whole osmiophilic material. The alterations of immature newborns are more severe than those of mature animals and also more severe after the longer life-time. These alterations are considered as a result of decreased synthesis of surface active phospholipids.