砷中毒对小鼠脑细胞内钙离子浓度影响的研究

目的:探讨砷中毒导致脑细胞损伤的机制。方法:采用尾静脉注射亚砷酸钠建立中毒动物模型,以Fluo-3/AM为细胞内游离钙离子的荧光指示剂,用激光扫描共聚焦显微镜测定脑细胞内Ca2+]i的含量变化,同时采用原子吸收分光光度计测定脑组织中砷(As)、用生化试剂盒测定超氧化物歧化酶(SOD)、丙二醛(MDA)的活性水平。结果:实验组小鼠脑细胞内的平均荧光强度明显高于对照组,实验组为116.10±33.75,对照组为42.78±22.66(P<0.001);实验组小鼠脑组织中As含量、MDA水平明显高于对照组,而SOD水平则低于对照组,两组差异有显著性意义(P<0.05)。结论:砷可增加小鼠脑细胞内的游离钙离子浓度,提示脑细胞内钙超载可能是其致脑细胞损伤的分子机制之一。

Effect of arseniasis in intracellular free Ca2+ concentration in isolated mouse brain cell

Objective: To study mechanism of arsenic poisoning induce injury in mouse brain cell.Methods: animal model of arsenic poisoning was establishment by caudal vein inject sodium arsenite.The changes of Ca~(2+)]i in mouse brain cells was measured by laser scanning confocal microscope using Fluo-3/AM as the calcium fluorescent indicator.and contents of As in brain tissues was measured by atomic absorption spectrophotometer,and level of superoxide dismutase(SOD) and malonaldehyde(MDA)in brain tissues was determined by biochemistry kit Results: Fluorescent intensity in mouse brain cells in arseniasis groups showed significantly higher than control group.The mean Fluorescent intensity in mouse brain cells in arseniasis groups was 116.10±33.75,while the control group was 42.78±22.66(P<0.001).and the contents of As and MDA in brain tissue in arseniasis groups were obviously higher than that of the control group,and the levels of SOD in arseniasis groups were markedly decreased than control group,there was significant difference between arseniasis groups and control groups(P<0.05).conclusions: the results indicates that arsenic could induce the intracellular free Ca~(2+) concentration in isolated mouse brain cell,and Ca~(2+) overload might be one of the molecular mechanism of brain cell injury by arsenic poisoning.