【作者】 李军琪；

【导师】 钟守国；

【作者基本信息】 泸州医学院 ， 眼科学， 2010， 硕士

【摘要】 目的：探讨用中波紫外线照射SD大鼠建立紫外线诱导的动物白内障模型及对比三种晶状体图像采集的效果,从而为进一步研究白内障的形成,混浊程度的评定及白内障的防治提供相关实验依据。方法：1.选用3月龄的一级大白鼠20只,随机分为实验组和对照组,实验组大鼠置于20×40×20cm3的笼中,笼子上方安置中波紫外线光源,光源距离大鼠约40cm,给予每天2小时中波紫外线照射；对照组不给于任何干预处理。选择不同照射时间段大鼠(0天、5天、20天、40天)摘取眼球去除角膜后在眼前节照相系统下采集晶状体混浊程度及晶状体核的颜色变化。然后环形剪下晶状体前囊膜,细胞面向上铺于玻片上,TUNEL法检测晶状体上皮细胞凋亡情况。观察晶状体上皮细胞的形态变化。2.另选4只大白鼠,用中波紫外线照射40天,采集眼球后对8只眼球同时选用三种方法采集白内障晶状体图像,并对比分析三种方法所获图像的效果。结果：1.眼前节照相系统观察晶状体：实验组结果显示经中波紫外线照射活体SD大鼠每天2小时,在第5天时晶状体保持透明、无明显混浊,随着照射时间的延长,在20天时出现皮质轻度混浊、多集中在“Y”字缝附近,呈现前部片状、羽毛状朝向赤道部的浅层皮质混浊,颜色呈白色,未见晶状体核的透明性及颜色改变。在40天时前囊下皮质混浊程度更加明显,前部浅皮质层及深皮质层均可观察到白色混浊,范围可以扩大到近赤道部；在手术摘取前囊膜时可见多数大鼠浅层混浊的皮质与前囊膜粘连较正常组紧密。40天照射组的晶状体核未发现有明显颜色变化。对照组未发现晶状体皮质及晶状体核有明显混浊和颜色的变化,仍保持其透明性。2. TUNEL细胞凋亡检测：DNA缺口末端原位检测部分大鼠晶状体上皮细胞发现经紫外线照射活体大鼠5天时即可发现晶状体前囊膜上皮细胞出现凋亡,凋亡的细胞呈棕黄色。3.细胞形态变化：5天组的细胞形态、大小与对照组相比无明显改变。40天组部分晶状体上皮细胞出现老化现象,可见大量的晶状体纤维与晶状体上皮细胞相连。4.对同一只白内障晶状体选用不同的三种晶状体采集方法获得晶状体图像,相比而言本实验设计的晶状体托板联合眼前节照相系统法采集的图像较其它两种方法获得的图像更清晰,结果稳定。结论：1.本实验方法成功实现了紫外线辐射性白内障大鼠模型的建立。2.中波紫外线是导致白内障发生的原因之一。3.晶状体混浊程度与中波紫外线照射的时间长短呈正相关。4.中波紫外线照射活体SD大鼠眼可以造成晶状体前囊膜上皮细胞凋亡。5.三种白内障晶状体图像采集方法各有优缺点,本实验采用黑色晶状体托板联合眼前节照相系统可以获得理想的晶状体图像,与其它两种方法相比较具有明显优势。更多还原

【Abstract】 Objectives:To set up UV-induced cataract model of SD rats and compare the effects of three kind of image acquisition on lens. Thereby provide correlated experimental basis for researching the formation, development, grades of cataract and prevention of cataract. Methods:1. three months-old first class rats (20subjects) were randomized to A or B group. Group A as experiment that put rats in the cage (20×40×20cm3) which was installed UVB lamp. The UVB lamp was 40cm from the rats. The rats was irradiated for 2 hours per day. Group B as control group that did nothing. Pick the rats’eye ball at different time:5-day,20-day,40-day, and remove corneal, and observe the degree of lens turbidity and the change of lens nucleus. Cut the anterior lens capsule roundly and pave it on the glass slide.Detect the apoptotic cells cells with TUNEL method in 20X high power field perimeter and observe the morphologic change of the lens epithelium cells.2. four other rats were selected to E grup for comparing the effects of three kind of image acquisition on lens. Results:1.Observe the lens with anterior eye segment image getting system:experimental group shows the SD rats’lens which receive UVB radiation 2 hours per day keep transparent at the 5th day. The cortex becoming feeble opacity and concentrate round anterior "Y"suture, peripheral cortex opacity as white lamellar anteriorly and featheriness toward ambitus, transparency and color change of the lens nucleus were not seen at days 20. The opacity is more obvious at anterior subcapsular cortex. white haze was seen at anterior peripheral cortex and deep cortex, and extend to ambitus at days 40. The superficial lamella cortex was adhered to anterior capsular more tightly than normal. And the 40-day’s radiation shows the color change was not obvios. On control group, the lens keep transparent each time.2. TUNEL apoptosis detection:TdT-mediated X-dUTP nick end labeling reflect that anterior lens capsule epithelium had apoptosis after radiation at 5th day, the apoptosis cells present claybank.3. Morphologic change of cells:The change of shape and size for non-apoptosis lens epithelium cells were not obvious compared with control group at 5th day. The aging phenomenon on lens epithelium cells appeared at 40th day as lens fiber grew out of the epithelium cells.4. the image got by using anterior eye segment image getting system combined with lens pallets were clearer than other tow methods Conclusions:1. By using ultraviolet B radiation we set up UV-induced cataract model in SD rats successfully.2. Ultraviolet B was one of the factors that cause cataract.3. There was a positive correlation between the degree of opacity and radiation lasting time.4. Ultraviolet B radiation can cause anterior lens epithelium cells apoptosis in vivo.5. Three methods of anterior eye segment image getting system each has merits and demerits. Anterior eye segment image getting system combined with lens pallets can get ideal lens images and has obvious superiority by contrast with other tow methods in our experiment.更多还原