Both synthesis and total content of lung elastin were measured after induction of interstitial pulmonary fibrosis in hamsters by a single intratracheal insufflation of amiodarone. Elastin synthesis, as measured by 14C-lysine incorporation into desmosine and isodesmosine, was significantly elevated (P less than 0.05) above control values for a 3-week interval after induction of lung injury. Total lung elastin content in the amiodarone-treated animals was 32% greater than in controls (P less than 0.05) 2 weeks after insufflation of the agent. Furthermore, the time course of elastin synthesis in this experimental model was similar to that observed in bleomycin-induced pulmonary fibrosis in hamsters. Increases in elastin may therefore be a common feature of interstitial pulmonary fibrosis and may contribute to the altered lung mechanics seen in this disease.