Abstract: BACKGROUND ＆ AIM:Studies on antiradiation effect of N-acetylcysteine in X-irradiated mouse. MATERIAL AND METHODS: In this dissertation,the antiradiation effect of pretreated NAC to mouse before X-irradiation were studied heamopoietic and immunological functions.RESULTS: NAC not only improve differentiation and proliferation of CFU-S,CFU-GM in bone marrow of mouse but also increase significantly the Con A-induced proliferation reaction of splenocytes and the spontaneous proliferation and the production of IL-2 of splenocytes induced by Con A in mouse exposed to different doses X-rays.CONCLUSION:NAC can increase significantly tolerance ability of antiradiation in mouse exposed to different doses x-rays.

Key words: N-acetylcysteine, X ray, damnification