ashkan salajegheh - Department of Radiology, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
mehdi hoseini - Medical Physics Department, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Mina Nouri - Department of Radiology, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran
Rasool Dehghani Soltani - Student Research Committee, Kerman University of Medical Sciences, Kerman- Iran

Introduction It has long been known that ionizing radiation can lead to detrimental effects in normal cells. In this light, Radioprotective chemicals have been used to decrease morbidity or mortality caused by ionizing irradiation. This study aimed to evaluate the radio-protective effect of N-acetylcysteineagainst radiation-induced mortality in male mice. Materials and Methods 52 healthy male mice were divided into four groups including NAC before irradiation (1), irradiation (2), NAC after irradiation (3) NAC before irradiation (4) and control. Three groups were treated orally with 100 mg/ kg of NAC. Gamma irradiation was performed at 8 Gy using a Co-60 machine. Kaplan-Meier method and the log-rank test were performed, using SPSS version 16. The significance level was considered to be 0.05. Results The statistical analysis revealed a significant difference between the test and control groups (P<0.05). The percentage of survival after 30 days was 46.2% for the irradiation group (1). In addition, the percentage of decreased lifespan was calculated at 5.90%, 23.60% and 17.93% for the first-third groups, respectively. Conclusion Results revealed lack of effectiveness of treatment with NAC after lethal dose. These results suggested that application of NAC for mice before irradiation protected them from the lethal effects of whole-body irradiation.

Gamma-Irradiation, Radioprotective, N-acetylcysteine, Radiation Sickness