Objective  Radiation-induced lung injury(RILI) is the most comon, dose-limiting complication in thoracic malignancy radiotherapy.Considering its negative impact on patients and restrictions to efficacy, the mechanism of RILI was studied.

  Methods  In this experiment, Wistar rats were locally irradiated with a single dose of 0, 16, or 20 Gy to the right half of the lung to establish a lung injury model.Two and six months after irradiation, the right half of the rat lung tissue was removed, and the concentrations of TGF-β 1, angiotensin Ⅱ, and aldosterone were determined via enzyme-linked immunosorbent assay.

  Results  Statistical differences were bserved in the expression levels of angiotensin Ⅱ and aldosterone between the non-irradiation and irradiation groups.Moreover, the expression level of the angiotensin Ⅱ-aldosterone system increased with increasing doses, and the difference was still observed as time progressed.

  Conclusion  Our preliminary Results demonstrate that the angiotensin Ⅱ-aldosterone system has an important pathophysiological function in the progression of RILI.However, further studies should be done to determine the mechanism of this progression.