摘要目的 研究β-淀粉样蛋白(Aβ)对原代培养的大鼠脑海马神经细胞内钙稳态相关蛋白Sorcin、RyR2mRNA的影响.方法 新生1-3天的Wistar大鼠,取其海马组织,原代培养8d后,用已老化过的Aβ25-35对海马神经细胞进行1μmol/L,10μmol/L和20 μmol/L剂量的染毒,培养24和48 h后分别观察海马神经细胞形态、和海马神经细胞内钙调节相关蛋白Sorcin、RyR2mRNA的基因表达水平.结果 随着Aβ25-35剂量的增加和染毒时间的延长,可发现随着Aβ25-35剂量的增加和染毒时间的延长,海马细胞出现细胞凋亡的比例增加,其中Aβ25-35 20 μmol/L染毒48 h培养海马细胞中出现了大量早期凋亡细胞和少量中期凋亡细胞.实时定量PCR结果显示,10 μmol/L Aβ5-35在对原代细胞染毒24和48 h后Sorcin mRNA的相对表达量为(1.42±0.03)和(1.63±0.02),与对照组相比,表达增加(P＜0.05);20μmol/L Aβ25-35在对原代细胞染毒24h和48 h后Sorcin mRNA的相对表达量(2.11±0.05)和(2.23±0.05),与对照组相比,表达增加(P＜0.05);20 μmo]/L Aβ25-35在对原代细胞染毒24和48h后RyR2mRNA的相对表达量为(1.64±0.03)和(1.95±0.03),表达显著高于对照组相(P＜0.05).结论 Aβ具有神经毒性,可抑制海马神经细胞的生长,可通过作用于钙调节相关蛋白的表达,诱发阿尔茨海默氏病(AD)的发生.

abstractsTo study the effects of β-amyloid (Aβ25-35) on calcium homeostasis related genes such as Sorcin and RyR2mRNA in primary cultured rats hippocampal neurons.Methods After 8 days of primary cultured,hippocampal neurons were exposure with different doses (1 μmol/L,10 μmol/L,and 20 μmol/L,respectively) of Aβ25-35,and 0 μmol/L dose as control group.After cultured 24h and 48h,observed hippocampal neuronal morphology by transmission electron microscope,detected the Sorcin and RyR2 gene relative expressions of the cultured hippocampal neurons by real-time PCR.Results With the increase of Aβ25-35 dose and exposure time,morphological changes of primary cultured hippocampal neurons were observed,showing the percentage of apoptosis neurons increased in the Aβ25-35 exposure groups.There were more apoptosis neurons in the Aβ20μmol/L group than other groups.The results of Real-time PCR showed Aβraised the expression of Sorcin mRNA and Ryr2 mRNA.The Sorcin mRNA relative expression were (1.42 ±0.03)and (1.63 ±0.02)when cultured 24h and 48h respectively in 10μmol/L Aβ2s-35 group;the Sorcin mRNA relative expression were (2.11 ± 0.05) and (2.23 ± 0.05) when cultured 24h and 48h respectively in 20μmol/L Aβ25-35 group;these results had statistically difference (P ＜ 0.05)compared with control group.The RyR2 mRNA relative expression were (1.64 ± 0.03) and (1.95 ± 0.03) when cultured 24h and 48h respectively in 20μmol/L Aβ25-35 group;These results also showed statistically difference compared with control group.Conclusion Aβ25-35 exhibits a neurotoxicity effect by inducing the apoptosis in primary cultured hippocampal neurons and inhibiting the growth of hippocampal neurons.It can induce AD by regulating the expression of calcium related proteins such as Sorcin and RyR.