睫状神经营养因子对谷氨酸引起海马神经细胞内游离Ca^(2+)浓度和P53蛋白表达的作用

EFFECT OF CNTF ON CONCENTRATIONS OF HIPPOCAMPAL INTRACELLULAR FREE Ca^(2+) AND EXPRESSION OF PROTEIN P53 INDUCED BY GLUTAMIC ACID

目的 :通过探讨睫状神经营养因子对谷氨酸引起海马神经细胞内游离 Ca2 + 浓度和 P53蛋白表达的作用 ,提供睫状神经营养因子存在非基因组快速作用途径 ,并对基因组信号转导产生影响的证据。方法 :用活细胞内荧光探针 Fura2 / AM实时检测睫状神经营养因子对谷氨酸引起海马神经细胞内游离 Ca2 + 浓度的影响 ,并用免疫组化方法观察睫状神经营养因子对谷氨酸引起海马神经细胞内 P53蛋白表达的作用。结果 :谷氨酸可引起海马神经细胞内游离 Ca2 + 浓度快速升高 ,并在 50 0μmol/ L-1范围内呈剂量依赖性。2 0 0μmol/ L-1的谷氨酸可上调 P53蛋白表达。睫状神经营养因子对静息条件下海马神经细胞内的游离 Ca2 + 浓度无显著改变。用睫状神经营养因子孵育 5min后 ,可快速压抑谷氨酸引起的胞内游离 Ca2 + 浓度升高 ,并下调 P53蛋白表达。结论 :睫状神经营养因子可能通过Ca2 +信号的快捷途径 。

To investigate the effect of ciliary neurotrophic factor(CNTF) on concentrations of hippocampal intracellular free Ca 2+ ([Ca 2+ ] i) and expression of protein P53 induced by glutamic acid. Methods: [Ca 2+ ] i and expression of protein P53 in the primary cultured hippocampal neurons were measured with the calcium sensitive fluorescent dye fura2/AM and immunohistochemical detection. Results: Glutamic acid rapidly induced increase of [Ca 2+ ] i. 200 μmol·L -1 glutamic acid upregulated expressin of prtoein P53. CNTF had no influence on [Ca 2+ ] i in resting condition. CNTF incubated for 5 min could repress increase of [Ca 2+ ] i induced rapidly by glutamic acid. And CNTF depressed expression of protein P53 for 10 h. Conclusion: It is probable that a rapid pathway of CNIF via Ca 2+ signal exists in the upstream of genomic signal transductive pathway.