升高细胞外钙离子能抑制和促进细胞凋亡的发生

Elevated Extracellular Calcium Can Prevent and Promote Apoptosis

钙离子是细胞分裂、生长、死亡过程中重要的信号传导分子 .为研究胞外钙离子与细胞凋亡的关系 ,将Ca2 + (5～ 7mmol)加入无血清培养液观察钙离子对无血清诱导人胚肺二倍体细胞株KMB17凋亡的影响 ;并将Ca2 + (5～ 7mmol)加入含体积分数为 2 %血清的脊髓灰质炎病毒 (poliovirus)生长培养液中 ,研究胞外钙离子对poliovirus诱导凋亡的影响 .经光学显微镜、荧光显微镜、细胞流式仪、电子显微镜分析 ,结果表明 :①加入钙离子的无血清培养未出现凋亡 ,而未加入钙离子的无血清培养则诱导典型的细胞凋亡症状 :细胞圆缩、细胞核浓缩破裂、核染色质凝缩后分布于核膜边缘呈新月状、在G0 /G1峰前出现典型的凋亡峰 .②与此相反 ,在po liovirus的培养液加入钙离子则反而促进poliovirus诱导的人胚肺二倍体细胞株KMB17凋亡的发生 ,表现在加入钙离子后 2 4h就出现凋亡 ,而未加入钙离子的在 48h后才出现凋亡 .首次报道同一细胞株在不同条件下 ,升高胞外钙离子即能抑制凋亡 ,又能促进凋亡 .

We elevated extracellular calcium (CaCl 2 5—7mmol ) to study the relationship between the calcium and apoptosis under different inducing conditions.The confluent human fibroblast (KMB 17 ) with extracellular calcium in serum free medium showed no apoptotic characteristics,but the cells without extracellular calcium in serum containing showed typical apoptotic characteristics.The confluent KMB 17 cells showed typical apoptosis 48?h after infection with poliovirus,but the confluent KMB 17 cells added with calcium(5—7mmol) showed ahead apoptotic characteristics 24?h after infection by poliovirus.The results demonstrated that the extracellular calcium can not only prevent,but also promote the apoptosis in a same cell strain under different inducing conditions.