<正> Objective: To explore the effects of γ-irradiation on mitogen-activated protein kinases （MAPKs） and role of intracellular calcium in this event in intestinal epithelial cell line 6 （IEC-6 cells）. Methods: After cultured rat IIEC-6 cells with or without the pretreatment of intracellular Ca2+ chelator were exposed to Y-ir-radiation of 6 Gy

the total and phosphorylated MAPKs in the cells were determined with Western blotting and apoptosis was examined with flow cytometry. Activities of Extracellular signal-regulated protein kinase （ERK） and p38 MAPK were determined by using immuoprecipitation followed by Western blotting. Results: In response to γ-irradiation

phosphorylation of ERK was not significantly observed

while the levels of phosphorylated c-Jun NH2-terminal kinase （JNK） and p38 MAPK were increased in 30 min and reached the peak 2 h after exposure to 6 Gy γ-irradiation

though the cell viability was significantly lowered 12 h. On the other hand

no obvious changes were seen in the total protei