Abstract:
Reduced levels of retinal dopamine, a key regulator of eye development, are associated with experimental myopia in various species, but are not seen in the myopic eyes of C57BL/6 mice, which are deficient in melatonin, a neurohormone having extensive interactions with dopamine. Here, we examined the relationship between form-deprivation myopia (FDM) and retinal dopamine levels in melatonin-proficient CBA/CaJ mice. We found that these mice exhibited a myopic refractive shift in form-deprived eyes, which was accompanied by altered retinal dopamine levels. When melatonin receptors were pharmacologically blocked, FDM could still be induced, but its magnitude was reduced, and retinal dopamine levels were no longer altered in FDM animals, indicating that melatonin-related changes in retinal dopamine levels contribute to FDM. Thus, FDM is mediated by both dopamine level-independent and melatonin-related dopamine level-dependent mechanisms in CBA/CaJ mice. The previously reported unaltered retinal dopamine levels in myopic C57BL/6 mice may be attributed to melatonin deficiency.
摘要:
视网膜多巴胺水平降低,眼睛发育的关键调控者,与各种物种的实验性近视有关,但在C57BL/6小鼠的近视眼中没有看到,它们缺乏褪黑激素,一种与多巴胺有广泛相互作用的神经激素。这里,我们在褪黑素丰富的CBA/CaJ小鼠中研究了形觉剥夺性近视(FDM)与视网膜多巴胺水平之间的关系.我们发现这些小鼠在缺乏形觉的眼睛中表现出近视屈光偏移,伴随着视网膜多巴胺水平的改变。当褪黑素受体被药理学阻断时,FDM仍然可以被诱导,但是它的大小减少了,在FDM动物中,视网膜多巴胺水平不再改变,表明褪黑激素相关的视网膜多巴胺水平变化有助于FDM。因此,在CBA/CaJ小鼠中,FDM由多巴胺水平非依赖性和褪黑激素相关的多巴胺水平依赖性机制介导。先前报道的近视C57BL/6小鼠中视网膜多巴胺水平未改变可能归因于褪黑激素缺乏。