MORPHOSTRUCTURAL CHANGES IN LUNG TISSUE IN AN EXPERIMENTAL MODEL OF SURFACTANT DEFICIENCY
Keywords:
surfactant deficiency; respiratory distress syndrome; type II alveolocytes; morphometry; lung structural changes; interstitial edema; fibrosisAbstract
Surfactant deficiency is a key pathogenetic factor not only in neonatal respiratory distress syndrome (RDS) but also in acute respiratory distress syndrome (ARDS) in adults. In this study, morphostructural changes in the lung tissue of rats were investigated using an experimental model of surfactant deficiency, applying histological and morphometric methods. The results demonstrated that in the experimental group, alveolar wall thickness increased by 75%, alveolar surface area decreased by 25%, and the number of type II alveolocytes decreased by 47%. Interstitial edema, inflammatory infiltration, and fibrosis processes were also observed. The deficit of type II alveolocytes and the suppression of surfactant synthesis led to the development of micro-atelectasis, reduction of gas exchange area, and worsening hypoxia. These alterations form the morphological basis of respiratory distress syndrome and are clinically associated with chronic respiratory failure and pneumosclerosis. The findings provide an important scientific basis for the development of new therapeutic strategies in the treatment of surfactant deficiency.
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