The normal electron histochemistry and the effect of hemorrhagic shock on the pulmonary surfactant system

An electron histochemical study was carried out on eight baboons to localize the phospholipid constituent of pulmonary surfactant in the normal state and after hemorrhagic shock. In the normal state, phospholipid was seen as a continuous layer lining the alveolar spaces. Phospholipid also was seen in the inclusion bodies of the granular pneumocytes, suggesting these cells as the site of production of surfactant. After hemorrhagic shock, the previously continuous phospholipid layer lining the alveolar spaces became totally fragmented. In addition, increased numbers of phospholipid particles were seen within the pulmonary interstitium. The results of this study suggest that the pulmonary surfactant system may be impaired after hemorrhagic shock.