苯甲酸雌二醇对大鼠视网膜缺血再灌注损伤后Bcl-2、Caspase-3蛋白表达的影响

发布时间：2018-03-05 12:23

本文选题：苯甲酸雌二醇　切入点：缺血再灌注　出处：《辽宁医学院》2012年硕士论文　论文类型：学位论文

【摘要】：目的探讨外源性雌激素对大鼠视网膜缺血再灌注损伤的保护作用机制及对Bcl-2和Caspase-3蛋白表达的影响。方法取72只雄性SD大鼠随机分为正常组（N），单纯缺血再灌注组（IR），苯甲酸雌二醇处理组(E2+IR)。其中后两组又分别分为再灌注后6h、24h、48h，72h组（每组8只）。通过升压装置增加大鼠前房压力建立大鼠视网膜缺血再灌注模型。对视网膜进行常规HE染色光学显微镜下观察视网膜组织形态变化，用免疫组织化学方法检测视网膜组织中bcl-2、caspase-3蛋白的表达变化情况，采用DNA原位末端标记（TUNEL）法检测视网膜组织中的调亡细胞。结果正常组大鼠视网膜组织，层次分明；缺血再灌注组6h时视网膜组织各层出现不同程度的水肿，神经节细胞层未见明显空泡样变性，内外核层细胞排列变得轻度疏松、杂乱；内外丛状层也可见轻度水肿；24h视网膜组织高度水肿，神经节细胞丢失严重，空泡样变性明显；内外核层细胞排列变得杂乱；内外丛状层增厚明显；48h后视网膜组织损害开始有所好转，72h时已经基本恢复正常形态，但整个视网膜组织已变薄。而苯甲酸雌二醇处理组，视网膜组织形态变化趋势与单纯缺血再灌注组相似，但视网膜组织损害程度在各时点较单纯缺血再灌注组有所好转，整个视网膜也较正常薄。正常组大鼠视网膜组织几乎无bcl-2、caspase-3蛋白的表达；单纯缺血再灌注组bcl-2和caspase-3蛋白在6h时已经开始表达，24h达高峰，48h表达开始下降，72h仍有部分表达；而苯甲酸雌二醇处理组caspase-3蛋白的表达在各时间点上较单纯再灌注组明显下调（P㩳0.01）；Bcl-2蛋白的表达在各时间点上较单纯再灌注组明显上调（P㩳0.01）；两组间比较均有统计学意义。正常视网膜组织几乎未见凋亡细胞的表达，在IR组，随时间的推移可见凋亡细胞增多，24h达高峰，48h有所减少；在E2+IR组，凋亡细胞表达的趋势同IR组但在各时间点上的表达均比IR组有所减少，两组比较均有统计学意义（P㩳0.01）。结论缺血再灌注损伤损害了视网膜组织结构，导致了大量凋亡细胞的产生。Bcl-2、Caspase-3参与了视网膜缺血再灌注损伤中细胞凋亡的调控，苯甲酸雌二醇可上调Bcl-2蛋白的表达下调caspase-3蛋白的表达，而抑制细胞调亡，，保护视网膜组织。
[Abstract]:Purpose. To investigate the protective mechanism of exogenous estrogen on retinal ischemia reperfusion injury in rats and the effect of exogenous estrogen on the expression of Bcl-2 and Caspase-3 protein. Method. Seventy-two male SD rats were randomly divided into normal group, ischemia reperfusion group, estradiol benzoate treatment group and estradiol benzoate treatment group. The retinal ischemia-reperfusion model of rats was established by atrial pressure. The retinal tissue morphology was observed under the optical microscope with routine HE staining. Immunohistochemical method was used to detect the expression of bcl-2caspase-3 protein in retinal tissue, and DNA in situ end labeling (Tunel) method was used to detect the apoptotic cells in retinal tissue. Results. In the normal group, there were different degrees of edema in each layer of the retina at 6 h after ischemia reperfusion, no vacuolar degeneration was found in the ganglion cell layer, and the arrangement of the cells in the inner and outer nuclear layer became slightly loose and chaotic. Mild edema was also seen in the inner and outer plexiform layer. The retinal tissue was highly edematous, the ganglion cells were lost seriously, vacuolar degeneration was obvious, and the cells of the inner and outer nuclear layer were disordered. After 48 hours of thickening of the inner and outer plexiform layer, the damage of retinal tissue began to improve, but the whole retinal tissue was thinned after 72 hours, while in the group treated with estradiol benzoate, The morphologic changes of retinal tissue were similar to those of simple ischemia-reperfusion group, but the degree of retinal tissue damage was improved at each time point compared with that of simple ischemia-reperfusion group. The whole retina was thinner than normal. There was almost no expression of bcl-2ncaspase-3 in normal rat retina, but the expression of bcl-2 and caspase-3 in ischemia reperfusion group began to peak at 6h and decreased at 48h. The expression of caspase-3 protein in estradiol benzoate treated group was significantly lower than that in reperfusion group at all time points. The expression of Bcl-2 protein was significantly up-regulated at each time point compared with that of reperfusion group. There was no apoptotic cell expression in normal retinal tissue, but in IR group, the number of apoptotic cells increased to a peak at 24 h and decreased at 48 h in IR group, while in E 2 IR group, the number of apoptotic cells increased to a peak at 24 h and decreased at 48 h. The expression trend of apoptotic cells was similar to that of IR group, but the expression of apoptotic cells in IR group was lower than that in IR group at each time point, and there was statistical significance between the two groups. 0.01g. Conclusion. Ischemia-reperfusion injury damaged the structure of retinal tissue and resulted in the production of a large number of apoptotic cells. Bcl-2Caspase-3 was involved in the regulation of apoptosis in retinal ischemia-reperfusion injury. Estradiol benzoate up-regulated the expression of Bcl-2 protein and down-regulated the expression of caspase-3 protein, inhibited cell apoptosis and protected retinal tissue.
【学位授予单位】：辽宁医学院
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R774.1

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