Lung Surfactant

**Semantic type:** Body Substance

**Definition:** Pulmonary surfactant lines the lung epithelium and lowers surface tension to prevent collapse at end-expiration. Deficiency of pulmonary surfactant results in respiratory distress syndrome (RDS) in premature infants. Lung surfactant is synthesized in alveolar type II cells, stored in lamellar bodies and secreted via exocytosis.

**Synonyms:** - LUNG SURFACTANT - Surfactant - Surfactant, Lung