Abstract:Objective:To study the hepatic gene expression profile early after 60^Co-γ irradiation in mice with eDNA microarray, in an attempt to understand the molecular mechanism of irradiation damage to liver in mice. Methods: Total RNA was extracted from mice liver 2 days after irradiation with ^60Co-γ ray and from normal mice liver. Hepatic gene expression patterns of irradiated and normal mice were compared with eDNA microarray(4 096 genes). RT-PCR was performed to validate the eDNA microarray results. Results: Compared with normal group, 124 genes showed a differential expression in irradiation group, with 46 genes upregulated(maily cell cycle and transcription regulation related proteins) and 78 down-regulated(mainly cytoskeletal genes). Of the 124 genes, 57 had identified functions and could be divided into 6 groups: DNA repair and stress response,cytoskeleton, hydronium channel/transport protein, signaling transduction, intermediary metabolism, and immune related proteins. RT-PCR analysis indicated that the expression of heat shock 70kD protein 5 (HspaS), RAS p21 protein activator 3 (Rasa3),and NAD(P)H dehydrogenase, quinone 1 (Nqol) were consistent with eDNA microarray data. Conclusion: Irradiation-induced hepatic injury is of multi-target and multi-pathway