铝对大鼠大脑皮层和海马神经细胞钙浓度影响

目的探讨染铝大鼠中枢神经系统中大脑皮层和海马神经细胞内游离钙浓度([Ca^2 ]i)的动态变化及可恢复性。方法对wistar大鼠进行亚慢性染毒，分别在染毒第45，75，120d和染毒结束后30d，应用钙离子荧光指示剂Fura-2／AM测定大鼠大脑皮层和海马神经细胞[Ca^2 ]i。结果中剂量组(74．7mg／kg)在染毒的各个时期内均表现为[Ca^2 ]i高于对照组，而高剂量组(248．7mg/kg)在染毒的第120d才表现为[Ca^2 ]i明显增高，低剂量组(37．3mg／kg)在各个染毒时期与对照组相比均无显著性差异。在停止接触铝30d后，各实验组与对照组相比无显著性差异，并且高、中剂量组表现出[Ca^2 ]i有降低的趋势。结论铝可通过逐渐增加大脑皮层和海马神经细胞内游离钙浓度([Ca^2 ]i)而发挥神经毒性作用。

Effect of aluminium on Ca2 + concentration in cerebral cortex and hippocamp neurons

Objective To explore the dynamic effect of aluminium on the concentration of extracellular Ca 2 in the cerebral cortex and hippocamp neurons. Methods Wistar rats were randomly divided into four groups based on their body weight.Aluminium chloride was administrered by oral at doses of 248 7,74 7,37 3 and 0?mg/kg for 120?days successively.Fura-2/AM calcium ions fluorescence indicator was used to measure concentration on Day 45,75,120 and 30 after stopping Al 3 exposure.Results 248 7 and 74 7?mg/kg groups had higher concentration of extracellular Ca 2 than the control group and the 37 3?mg/kg group had no significant difference between the control group.And if stopping Al 3 exposure,the concentration would recover.Conclusion Al 3 can show the neurotoxic effect by raising the concentration of extracellular Ca 2 in the cerebral cortex and hippocamp neurons.