氚水β射线照射对大鼠胚胎脑细胞增殖的影响

Cell Proliferation of Neurons in Fetal Brain in Rat Exposed in Vitro to β Radiation from HTO

采用流式细胞术、MTT方法、细胞色素C还原法、逆转录-聚合酶链式反应(RT-PCR)及脉冲电场凝胶电泳方法(PFGE),分别检测大鼠受0～3.7×106Bq/mL氚水(HTO)作用后神经元细胞的凋亡、增殖抑制、超氧阴离子(O2-)释放、p53基因表达与DNA断裂损伤,观察氚水β射线照射对体外培养大鼠胚胎脑细胞的损伤效应。结果显示,随着氚水放射性浓度的增大,神经元细胞的凋亡率、增殖抑制率与p53mRNA表达量均增大,DNA断裂损伤程度随之加重,而O2-释放量随之减少。这说明氚水β辐射能使神经元细胞DNA双链断裂、促进其p53基因表达引发细胞凋亡及减少O2-释放来抑制增殖。

Flow cytometry,MTT method,cytochrome C reduction,RT-PCR and pulsed field gel electrophoresis（PFGE）were used respectively to determine apoptosis,the inhibition of cell proliferation,the release of superoxide anion（O2-）,the expression of p53 gene and DNA double strand break（DSBs）to investigate the insults to neurons in fetal brain in rat exposed in vitro to 0—3.7×106 Bq/ml of tritiated water（HTO）.Results showed that apoptotic rate,inhibition rate of cell proliferation and expression of p53 mRNA of neurons all increased with the increment of radiation concentration of HTO,in parallel,the extent of DSBs in neurons also aggravated with enlarged dose.But the release quantity of O2-decreased with enlarged dose.All those suggested that HTO β radiation could inhibit the proliferation of neurons via the apoptosis induced by DSBs and p53 gene expression and the decrease of release of O2-.