ALVEOLAR CELLS IN CYCLOPHOSPHAMIDE-INDUCED LUNG INJURY - AN ULTRASTRUCTURAL ANALYSIS OF TYPE-II ALVEOLAR EPITHELIAL-CELLS IN-SITU

Recent studies have brought rich evidence in favour of the significant contribution of the surfactant system-forming structures to morphogen esis of many pulmonary disorders. The aim of this study was to evaluat e the effect of intraperitoneal cyclophosphamide administration on cha nges within this system. The experiments used 40 Wistar rats, of 170g body weight. The animals were divided into two experimental groups. Gr oup I animals were given cyclophosphamide (Endoxan-ASTA) in a single i ntraperitoneal dose of 150mg/1kg b.w./1ml PBS/. Group II (control) rec eived 1ml PBS. All the animals were sacrificed after 1, 3, 7 and 28 da ys following intraperitoneal cyclophosphamide or PBS administration. M orphological examinations of pulmonary tissue were based on ultrastruc tural analysis in the transmission electron microscope. The study reve aled that a single intraperitoneal cyclophosphamide injection caused d amage to all elements forming the surfactant system, particularly to t ype II alveolar epithelial cells. Rebuilding processes in pulmonary ti ssue, coexisting with destructive changes, occurred with a significant contribution of type II alveolar epithelial cells. These cells are li kely to take an active part in pulmonary fibrosis processes observed a fter the action of cyclophosphamide.