细胞凋亡过程中细胞内Ca^(2+)和蛋白激酶C浓度的改变

Changes of [Ca^(2+)]i and protein kinase C levels in the process of adriamycin induced apoptosis of MEC-1 cells

目的 :探讨阿霉素诱导人涎腺癌细胞凋亡过程中细胞游离Ca2 + ([Ca2 + ]i)和蛋白激酶C(PKC)浓度的变化特点和意义。方法 :选择阿霉素诱导人涎腺粘液表皮样癌细胞凋亡 ,采用光镜、电镜、琼脂糖凝胶电泳和流式细胞仪检测凋亡 ;同时流式细胞检测细胞内 [Ca2 + ]i,Bradford法测定PKC浓度。结果 :阿霉素作用于人涎腺粘液表皮样癌细胞系MEC 1细胞 2 4h出现典型的凋亡改变。细胞凋亡过程中 ,胞内 [Ca2 + ]i明显升高 ;而PKC浓度在凋亡早期明显升高 ,到凋亡晚期则明显降低。结论 :细胞内 [Ca2 + ]i和PKC浓度的改变是阿霉素诱导涎腺细胞凋亡的主要机制 。

Objective: To study the significance of intracellular free calcium levels ([Ca 2+]i) and protein kinase C(PKC) levels in the process of human salivary gland mucoepidermoid carcinoma MEC-1 cell apoptosis induced by adriamycin. Methods: MEC-1 cells were treated with adriamycin at 10 μmol/L for 30 s～24 h.Apoptosis of the cells was investigated by light and electron microscopy, agarose gel electrophoresis and flow cytometry. [Ca 2+]i was determined by flow cytomerty, PKC by Bardford method. Results: The results showed that MEC-1 cells presented classic morphologic features of apoptosis. [Ca 2+]i in the treated cells was increased from (36.63±0.61) nmol/L to (84.00±0.45) nmol/L after 30 s～24 h treatment,while that in the control cells was 17.43±0.47 (P<0.01).PKC in the control cells was (96.25±2.75) pmol/(min·mg),in the 30 s treatment cells (126.54± 4.33) pmol/(min·mg) and decreased to 57.38±3.28 in the 24 h treatment cells (P<0.01). Conclusion: [Ca 2+]i and PKC may play roles in the adriamycin induced apoptosis of MEC-1 cells.