Most teleost fishes possess a unique system for tissue oxygen supply, where oxygen is delivered to the retina at partial pressures that exceed one atmosphere, providing a steep gradient for oxygen diffusion through their thick avascular retinas. This exceptional physiological system works through the elaborate interplay between highly pH-sensitive hemoglobins, acid-producing metabolic pathways, and a retinal vasculature with specialized structural and functional properties. This graphical review summarizes recent advances in understanding the mechanisms underlying retinal oxygen secretion and their impact on visual processing. Further, it discusses how the evolution of this complex physiological system provided the essential physiological exaptations for the adaptive improvements of vision in early teleost evolution. Finally, it summarizes knowledge gaps and directions for future research on this unique system for tissue oxygen supply.

大多数硬骨鱼类拥有独特的组织氧气供应系统，其中氧气以超过一个大气压的分压被输送到视网膜，从而为氧气扩散通过其厚的无血管视网膜提供陡峭的梯度。这种非凡的生理系统通过高度pH敏感的血红蛋白，产酸的代谢途径以及具有特殊结构和功能特性的视网膜脉管系统之间的复杂相互作用而起作用。该图形综述总结了在了解视网膜氧分泌的基础机制及其对视觉处理的影响方面的最新进展。此外，它讨论了这个复杂的生理系统的进化如何为硬骨鱼早期进化中的视觉适应性改善提供必要的生理学解释。最后，