The corneal surface of aquatic vertebrates: microstructures with optical and nutritional function?
The corneal surface of aquatic vertebrates: microstructures with optical and nutritional function?
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DOI：
10.1098/rstb.2000.0661
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发表时间：
2000-09-29
期刊：
影响因子：
--
通讯作者：
Collin, SP
中科院分区：
文献类型：
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作者：
Collin, HB;Collin, SP
哺乳动物角膜的前表面在维持平滑的光学界面和因此的清晰的视网膜图像方面起着重要作用。光滑的表面是由泪膜产生的，泪膜粘附在各种微突起上，这些微突起增加了细胞表面积，改善了对氧气和营养物质的吸收，并有助于代谢产物穿过外细胞膜的运动。然而，很少有人知道在其他脊椎动物从不同的环境中提供的结构适应和lear膜支持。利用场发射扫描电子显微镜，这项研究）;检查角膜上皮细胞的密度和表面结构的代表性物种的类Cephalaspidomorphi，软骨鱼类，硬骨鱼，两栖类，爬行类，鸟类和哺乳动物，包括一些有袋类。细胞密度和微孔，微脊，microplicae和微绒毛的结构和发生的变化描述相对于放置在角膜上的要求，在不同的水生环境，如海洋和淡水。上皮细胞密度逐渐减少，（例如多佛鳎Microstomius pacificus的29 348个细胞mm（-2（例如，黑鲷中的5999个细胞mm（-2））到陆地细胞（例如，在澳大利亚考拉Phascolarctos cinereus中的2126个细胞mm（-2））脊椎动物中，表明穿过角膜表面的渗透应力的降低。：在南半球七鳃鳗，即囊七鳃鳗（Geotriaaustralis）和短头七鳃鳗（Mordaciamordax）中发现的微孔代表用于释放粘液的开口，粘液可以保护角膜在它们的挖洞阶段免受磨损。作为海洋硬骨鱼的特征，角膜微脊的指纹状图案是一种普遍存在的特征，覆盖许多类型的感觉上皮（包括嗅觉上皮和口腔粘膜）。与微皱襞和微绒毛一样，微脊稳定泪膜以保持光滑的光学表面并增加上皮的表面积，有助于扩散和主动运输。角膜表面结构的明显种间差异表明角膜泪液的组成和稳定性具有适应性可塑性。在各种水生环境中拍摄。
The anterior surface of the mammalian cornea plays an important role in maintaining a smooth optical interface and consequently a sharp retinal image. The smooth surface is produced by a tear film, which adheres to a variety of microprojections, which increase the cell surface area, improve the absorbance of oxygen and nutrients and aid in the movement of metabolic products across the outer cell membrane. However, little is known of the structural adaptations and lear film support provided in other vertebrates from different environments. Using field emission scanning electron microscopy, this stud); examines the density and surface structure of corneal epithelial cells in representative species of the classes Cephalaspidomorphi, Chondrichthyes, Osteichthyes, Amphibia, Reptilia, Aves and Mammalia, including some Marsupialia. Variations in cell density and the structure and occurrence of microholes, microridges, microplicae and microvilli are described with respect to the demands placed upon the cornea in different aquatic environments such as marine and freshwater. A progressive decrease in epithelial cell density occurs from marine (e.g. 29 348 cells mm(-2) in the Dover sole Microstomius pacificus) to estuarine or freshwater (e.g. 5999 cells mm(-2) in the black bream Acanthopagrus butcheri) to terrestrial (e.g. 2126 cells mm(-2) in the Australian koala Phascolarctos cinereus) vertebrates, indicating the reduction in osmotic stress across the corneal surface. Tilt: microholes found ill the Southern Hemisphere lampreys, namely the pouched lamprey (Geotria australis) and the shorthead lamprey (Mordacia mordax) represent openings for the release of mucus, which may protect the cornea from abrasion during their burrowing phase. Characteristic of marine teleosts, fingerprint-like patterns of corneal microridges are a ubiquitous feature, covering many types of sensory epithelia (including the olfactory epithelium and the oral mucosa). Like microplicae and microvilli, microridges stabilize the tear film to maintain a smooth optical surface and increase the surface area of the epithelium, assisting in diffusion and active transport. The clear interspecific differences in corneal surface structure suggest an adaptive plasticity in the composition and stabilization of the corneal tear. film in various aquatic environments.