持续高眼压波动引起小梁网结构改变的研究

发布时间：2018-04-25 05:10

本文选题：原发性开角型青光眼 + 眼压波动　；参考：《第三军医大学》2014年博士论文

【摘要】：研究背景青光眼是一组以视野缺损为特征的视神经病变，高眼压是最重要的危险因素。当前最主要的治疗方式是通过各种方法降低眼压，减慢疾病的进程。在原发性开角型青光眼（primary open-angle glaucoma，POAG）中，小梁网组织发生病理性改变是主要的致病原因，小梁网组织细胞外基质发生堆积、小梁柱之间的空间减少、密度增加，小梁网细胞功能发生障碍，导致房水流经小梁网时阻力增大，引起了高眼压。但是到目前为止，导致青光眼小梁网组织发生病变的原因和机制仍然未知。小梁网桥接于巩膜突和角膜后弹力层之间，由多孔的、扁平的胶原板层构成类似海绵状的结构，小梁细胞粘附于小梁网的小柱中，中间无血管组织。由睫状体产生的房水必须经过小梁网组织，才能到达其外侧的苏氏管。小梁网的管旁组织和苏氏管的内侧是房水流出阻力的主要产生部位，并对眼压有重要调节功能。由于小梁网独特的物理位置及组织结构，自分泌和旁分泌是小梁网细胞对房水阻力调节的主要方式。在POAG中，许多细胞因子、化合物、核苷对房水的流出有不同程度的调节作用，并对小梁网的结构产生影响，但是如何触发这些物质在眼部的释放还不清楚。在健康人群中，眼压存在着生物节律性波动和日常生活引起的无规律性波动。由于眼压的波动和房水的流出，小梁网组织承受着多种形式的生物力。在组织发育和形态的维持过程中，生物力对细胞有重要的调节作用，能够改变组织的结构和功能。研究证实，原发性开角型青光眼患者的眼压波动比健康人群要大得多。小梁网细胞是一种力学敏感型细胞，眼压大幅波动引起的小梁网组织形态的变化产生的生物力，同样会对小梁网细胞和小梁网组织产生重要的影响。因此，我们推测，早期大幅的眼压波动可能引起原发性开角型青光眼小梁网组织病变，成为后期高眼压症和青光眼的发生的一个重要原因。为了检验这一假设，本课题从以下三个方面展开研究：1、建立眼压波动的SD大鼠模型，证实小梁网组织的改变可源于眼压波动，而非模型建立过程中的损伤。2、证实眼压经过一段时间大幅度的波动后，小梁网的形态、细胞外基质及肌动蛋白表达发生类似于原发性开角型青光眼小梁网样的改变。3、探讨眼压波动后引起小梁网细胞改变的力学信号传导通路。研究目的通过建立大鼠眼压波动的动物模型，证实高眼压波动能引起小梁网形态、细胞外基质、肌动蛋白等发生类似POAG小梁网样改变，并初步探讨导致其改变的小梁网细胞信号传导通路。研究方法 1.对大鼠巩膜进行连续14天的钳夹，造成眼压波动，利用HE染色检测角膜、巩膜、视网膜神经节细胞的损伤情况及小梁网形态改变情况，ELISA检测房水IL-6浓度，组化染色检测CD45阳性细胞，确定小梁网的形态改变源于眼压波动而非机械损伤；2.对巩膜进行连续28天的钳夹造成眼压波动，利用HE染色检测角膜、巩膜、视网膜神经节细胞的损伤情况及小梁网形态改变情况，组化染色检测小梁网细胞外基质蛋白及肌动蛋白表达变化情况；3.对巩膜进行连续28天的钳夹造成眼压波动，组化染色检测常规力信号传导蛋白的表达及变化情况。研究结果 1.经过14天的眼压波动后，角膜厚度、巩膜厚度、视网膜神经节细胞密度没有发生改变，房水IL-6浓度无明显改变，小梁网组织中无CD45阳性细胞表达，小梁网密度增加；2.经过28天眼压波动后，角膜厚度、巩膜厚度、视网膜神经节细胞密度没有发生改变，小梁网肌动蛋白、纤维连接蛋白、层粘连蛋白表达上调，小梁网密度增加，眼压和小梁网厚度无明显变化；3.经过28天的眼压波动，小梁网组织中Rho A和ERKs表达上调，JNK和Beta-catenin无表达。结论 1.眼压波动模型中小梁网组织发生的改变源于眼压波动，而非建立模型过程中的机械损伤刺激；2.眼压的波动可以引起小梁网组织中肌动蛋白增加，细胞外基质蛋白沉积，，造成小梁网密度增加等类似于POAG小梁网样改变；3.眼压波动引发Rho A和ERKs等信号蛋白的激活，可能是导致小梁网组织发生改变的机制。
[Abstract]:Background of the study

In primary open - angle glaucoma ( POAG ) , there is a major risk factor for glaucoma . In primary open - angle glaucoma ( POAG ) , there is a major cause of disease . In primary open - angle glaucoma ( POAG ) , there is a major cause of disease change . In primary open - angle glaucoma ( POAG ) , the small beam network tissue has a reduced space , the density is increased , and the function of small beam network cells is increased , causing high intraocular pressure .

In POAG , many cytokines , compounds and nucleotides regulate the outflow of aqueous humor to different degrees and have an important effect on the structure of trabecular , but how to trigger the release of these substances in the eye is not clear .

Because of the fluctuation of intraocular pressure and the outflow of aqueous humor , the small beam network tissue is subject to various forms of biological force . In the process of maintaining tissue development and morphology , the biological force plays an important role in regulating the structure and function of tissue .

In order to test the hypothesis , this topic is studied from three aspects : 1 . To establish an SD rat model of intraocular pressure fluctuation . It is proved that the changes of trabecular - net tissue can be derived from the fluctuation of intraocular pressure , rather than the damage in the establishment of the model .

Purpose of study

By establishing an animal model of intraocular pressure fluctuations in rats , it was confirmed that high intraocular pressure fluctuations could cause similar changes in trabecular morphology , extracellular matrix , actin , and the like , similar to that of POAG , and to initially probe into the cell signal transduction pathways leading to changes .

Research Methods

1 . The rat sclera was clamped for 14 days , which caused the fluctuation of intraocular pressure . Using HE staining to detect the damage of cornea , sclera , retinal ganglion cells and the morphological changes of small beam , ELISA was used to detect the concentration of IL - 6 in aqueous humor .
2 . The ocular pressure fluctuation was caused by the continuous 28 - day clamping of sclera , the damage of cornea , sclera and retinal ganglion cells was detected by HE staining , and the morphological changes of trabecular morphology were detected , and the changes of extracellular matrix protein and actin expression were detected by histochemical staining .
3 . The intraocular pressure fluctuation was caused by the continuous 28 - day clamping of sclera , and the expression and change of normal force signal transduction protein were detected by histochemical staining .

Results of the study

1 . After 14 days of intraocular pressure fluctuation , the corneal thickness , scleral thickness , retinal ganglion cell density did not change , the concentration of IL - 6 in aqueous humor was not changed , there was no expression of cd45 - positive cells in trabecular - net tissue , and the trabecular - net density increased ;
2 . After 28 days of intraocular pressure fluctuation , the corneal thickness , scleral thickness and retinal ganglion cell density were not changed . The expression of actin , fibronectin and laminin in trabecular network was up - regulated .
3 . After 28 days of intraocular pressure fluctuation , there was an up - regulation of the expression of rho - A and ERKs in trabecular - net tissue , and no expression was found in the expression of 伪 - catenin and 尾 - catenin .

Conclusion

1 . The change of trabecular - net structure in the model of intraocular pressure fluctuation is caused by the fluctuation of intraocular pressure , rather than mechanical damage stimulation in the process of establishing the model ;
2 . The fluctuation of intraocular pressure can cause the increase of actin and the deposition of extracellular matrix protein in small beam network tissue .
3 . The activation of signal proteins , such as rho A and ERKs , can be caused by intraocular pressure fluctuation , which may be a mechanism that can cause changes in trabecular network tissue .

【学位授予单位】：第三军医大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：R775.2

【引证文献】