Radiation-induced fibrosis in rat lung: Modification by hydroxypiperquin phosphate

Purpose: To evaluate the HPQP as a modifier of radiation-induced pulmonary fibrosis in rats sacrificed 4 months and 6 months separately after a single dose of 0, 15, 20, 25 Gy60Co r rays to the right hemithorax. Methods: HPQP was administered by a stomach tube 2 times a week after irradiation at a regimen of 100mg/kg. Pulmonary fibrosis was evaluated by lung hydroxyproline( HP) content and histological observation( LM and EM). Results: The content of lung HP increased with increasing radiation dose. The differences between control group and 20,25 Gy group are significant P 0. 01). Cotreatment with HPQP significantly ameliorated this response (P 0. 01). The intensity of pulmonary pathological changes increased with increasing radiation dose also, and HPQP can lessen these changes greatly. Conclusions: HPQP may inhibit the progression of lung fibrosis and that the clinical application of HPQP is somehow evidenced by this study. This experiment also established an animal model of radiation-induced pulmonary fibrosis successfully.