■本研究调查了眼睑缝合近视(LSM)大鼠内在光敏性视网膜神经节细胞(ipRGC)和多巴胺能无长突细胞(DAC)的变化。
■通过缝合右眼4周在大鼠中诱导LSM。对整装视网膜中的ipRGC和DAC进行双重免疫荧光染色,以分析对照的密度和形态变化,LSM,和同伴的眼睛。采用实时定量PCR和Westernblotting检测相关基因和蛋白表达水平。
■眼睑缝合的眼睛引起了严重的近视,但是同伴的眼睛并没有不同的控制。在LSM大鼠视网膜的LSM和对眼中都观察到ipRGC密度降低,总体黑视素表达矛盾地增加,树突状珠子增大。相比之下,DAC的变化只发生在LSM的眼睛,随着DAC密度和酪氨酸羟化酶(TH)表达的降低,稀疏的树枝状过程,更少的静脉曲张。有趣的是,在LSM眼中,内丛状层(IPL)中ipRGC与DAC之间的接触以及垂体腺苷酸环化酶激活多肽(PACAP)和囊泡单胺转运蛋白2(VMAT2)mRNA的表达减少。
■LSM大鼠视网膜中的ipRGC和DAC在密度上经历了多次改变,形态学,和相关的分子表达。然而,单靠ipRGC的改变似乎不是近视发展所必需的,鉴于近视仅在眼睑缝合的眼睛中引起,他们不太可能独自推动DAC的变化。LSM眼中ipRGC和DAC之间的接触减少可能是它们之间信号传导受损的结构基础。PACAP和VMAT2,与ipRGC和DAC密切相关,可能通过复杂的机制在LSM中发挥重要作用。
UNASSIGNED: This study investigates alterations in intrinsically photosensitive retinal ganglion cells (ipRGCs) and dopaminergic amacrine cells (DACs) in lid suture myopia (LSM) rats.
UNASSIGNED: LSM was induced in rats by suturing the right eyes for 4 weeks. Double immunofluorescence staining of ipRGCs and DACs in whole-mount retinas was performed to analyze changes in the density and morphology of control, LSM, and fellow eyes. Real-time quantitative PCR and Western blotting were used to detect related genes and protein expression levels.
UNASSIGNED: Significant myopia was induced in the lid-sutured eye, but the fellow eye was not different to control. Decreased ipRGC density with paradoxically increased overall melanopsin expression and enlarged dendritic beads was observed in both the LSM and fellow eyes of the LSM rat retinas. In contrast, DAC changes occurred only in the LSM eyes, with reduced DAC density and tyrosine hydroxylase (TH) expression, sparser dendritic processes, and fewer varicosities. Interestingly, contacts between ipRGCs and DACs in the inner plexiform layer (IPL) and the expression of pituitary adenylate cyclase-activating polypeptide (PACAP) and vesicular monoamine transporter protein 2 (VMAT2) mRNA were decreased in the LSM eyes.
UNASSIGNED: The ipRGCs and DACs in LSM rat retinas undergo multiple alterations in density, morphology, and related molecule expressions. However, the ipRGC changes alone appear not to be required for the development of myopia, given that myopia is only induced in the lid-sutured eye, and they are unlikely alone to drive the DAC changes. Reduced contacts between ipRGCs and DACs in the LSM eyes may be the structural foundation for the impaired signaling between them. PACAP and VMAT2, strongly associated with ipRGCs and DACs, may play important roles in LSM through complex mechanisms.