超氧阴离子自由基对大鼠肝卵圆细胞胞内自由钙浓度的影响

采用激光共聚焦扫描显微镜，观察黄嘌呤黄嘌呤氧化酶反应系统（Ｘ／ＸＯ）生成不同浓度的超氧阴离子自由基（Ｏ２）致培养的大鼠肝卵圆细胞（ＷＢ细胞）胞质内钙浓度的变化，结果发现：仅小剂量的Ｏ２引起胞质内钙浓度升高，约３０Ｓ后达到峰值，６０ｓ后恢复正常。部分细胞观察到数次钙浓度间断升高、幅度逐渐下降的现象。超氧化物歧化酶（ＳＯＤ）可抑制此变化，过氧化氢酶（ＣＡＴ）无效果，细胞在无钙液中观察仍出现钙峰，但受

Effect of superoxide anions on intracellular free calcium concentration in rat liver oval cells

The effects of superoxide anion (O2) of various concentrations generated by interaction of xanthine with xanthine oxidase (X/XO) on dynamic changes of intracellular free calcium concentration(Ca2 ]i) in cultural rat liver oval cells (WB cells) were investigated by fluorescence of Fluo-3 combined with Ca2 on laser scanning conforcal microscopy. The results showed that a rapid Ca2 ]i increase occured after treatment withO2 of low concentration (X: 200 mol/L, XO: 0.2mu/mL) immediately, top of the Ca2 1i appeared at thirty seconds after treatment and returned to normal at sixty seconds. In some of the cells, a decaying Ca2 ], oscillating could be ovserved, but no any changes of the Ca2 ], appeared in the cells which were treated by O2of middle and high concentration (X: 200 mol/L, XO: 5mu/mL and X: 500 mol/L, XO: 20mu/mL). The changes of Ca2 ]i were inhibited by superoxide dismutase (SOD), but catalase (CAT) not. The cells experimented in tile mediUm of D-Hank's with EGTA were observed the change of Ca2 ]. also, but the changes were blocked in the normal medium with thapsigangin, which depleted Ca' J. stores. The results Suggest that the changes of Ca2 ]. induCed by O2of low concentration might due to the role of intracellular Ca2 pools release and they might be related to action of cellular signal transduction induced by O2which could stimulate proliferation or transformation of the cell.