Study on the effects of stress hormone and endocrine disrupter on an organism using the technology in neuroscience

本课题的目的是研究应激激素和内分泌干扰物对神经组织微观结构的影响。第四章将新的成像方法应用于活体海马片，显示了长时程增强(LTP)的时空模式。这将是研究这类内分泌干扰物作用下大脑的有力手段。本文研究了壬基酚对PC12细胞凋亡的影响。采用原位末端标记法和DNA片段化分析方法，研究了壬基酚对血清剥夺诱导PC12细胞凋亡的影响。此外，还观察了促凋亡因子Bad、Bax和抗凋亡因子Bcl2含量及caspase 3酶活性的变化。低于100 ng/ml的壬基酚可增加TUNEL信号、DNA片段化和促凋亡因子的含量，与无血清剥夺组比较，差异有统计学意义。此外，加入壬基酚可增强caspase-3的活性，而caspase-3的抑制剂Z-VAD可减弱这种作用。这些结果表明，低于100 ng/ml的壬基酚通过激活caspase-3来增强血清剥夺诱导的PC12细胞的凋亡。此外，还利用PC12和CHO细胞研究了细胞凋亡相关因素的变化。分别用6OHDA或不加FBS诱导细胞凋亡。原位末端标记法检测细胞凋亡率，RT-PCR法检测细胞凋亡相关因子Bax、Bcl2的m-RNA表达。100 nM和10μM的皮质醇对细胞凋亡有抑制作用。与对照组相比，Bax蛋白表达明显增强(P&lt；0.1)。

The object of this project was to study the effect of the stress hormones and the endocrine disrupters to the microscopic structure of nerve tissue.New imaging method was applied to the living hippocampal slices in the chapter 4. It showed spatiotemporal patterns of the long-term potentiation (LTP). It will be the strong method to study the brain under the effect of such endocrine disrupters.The effect of nonylphenol on apoptosis in PC12 cells was studied. We investigated effect of nonylphenol on apoptosis induced by serum deprivation in PC12 cells using TUNEL and DNA fragmentation assays. In addition, changes in contents of proapoptotic factors, Bad and Bax, and antiapoptotic factor, Bcl-2, and enzyme activity of caspase-3 were studied. Below 100 ng/ml of nonylphenol increased TUNEL signals, DNA fragmentation and content of proapoptoticfactor, Bad as compared to those by serum deprivation without nonylphenol. Furthermore, addition of nonylphenol enhanced caspase-3 activity and Z-VAD, caspase-3 inhibitor, diminished such effect. These results indicated that below 100 ng/ml of nonylphenol enhanced apoptosis induced by serum deprivation via caspase-3 activation in PC12 cell.The changes of apoptosis of cultured cells are investigated under the existence of small quantities of cortisol. Moreover the changes of the relational factors of the apoptosis were also studied using PC12 or CHO cells. The apoptosis was induced with 6OHDA or without FBS. On set of the apoptosis was measured by TUNEL method, The RT-PCR method was used to measure the m-RNA of apoptosis related factors Bax and Bcl-2. 100 nM and 10μM of cortisol inhibits the apoptosis. The signals of Bax showed significant increase compared with control (P<0.1).