目的:本研究的目的在探討維生素K□(menadione)單獨或併用游離輻射對於人類肝癌Hep3B細胞之殺傷作用。時之存活曲線，合併處理之方式如下:先給予35μM維生素K□三小時再輻射照射;或先輻射照射再給予維生素K□;或在維生素K□存在下，同時給予輻射照射。濃度(IC□)約為60μM。以10-100μM維生素K□處理Hep3B細胞三小時後，細胞內還原態麩胱甘□顯著降低。以2Gy以上劑量與維生素K□合併處理時，Hep3B之存活分率大部份都降至15%以下，顯著增加癌細胞死亡的效果。生素K□存在的同時給予輻射照射

　　　　　Purpose: To study the killing effects of menadione alone or combined withionizing radiation on human hepatoma Hep3B cell.ionizing radiation or the combination of both agents. Three protocols for combinedtreatments : first, cells were pre-treated with 35 μM menadione for 3 hours thenirradiated; second, cells were irradiated followed by the menadione treatment: third,cells were concurrently treated with both agents.around 60 μM. The intracellular reduced glutathione was significantly decreasedafter menadione treatment for 3 hours. After combined treatment most survivingfractions were less than 15%.treatment' have synergistic effect. However, 'pre-treatment of menadione followedby irradiation' only has the addition effect. This finding may be useful for clinicalapplication of menadione when combined with ionizing radiation to treat cancers.