Abstract
Purpose:
To study the retinal cellular basis of amblyopia, a developmental disease that is characterized by impaired visual acuity. The presented work was undertaken to ex-amine the retinal transcripts associated with amblyopia in rats with experimentally in-duced unilateral amblyopia.
Methods:
Surgical tarsorrhaphy was performed in the eye lids of Sprague-Dawley (SD) rats were sutured on the left side prior to eye opening at postnatal day 14 with the contralateral eye serving as the corresponding control. This condition was maintained for over 2 months, after which electroretinograms (ERGs) were recorded, the retinal ganglion cell (RGC) arrangement and number were determined using neuroanatomical tracing, the retinal transcripts were studied using microarray analysis. Regulated mRNAs were confirmed with quantitative reverse-transcriptase PCR, and selected proteins were studied using immunohistochemistry.
Results:
We found an attenuated ERG in eyes that were deprived of visual experience. Retrograde neuroanatomical staining disclosed a significantly higher number of RGCs within the retina on the visually deprived side, as well as a multilayered distribution of RGCs in comparison to nondeprived samples. At the molecular level, several transcripts were either up- or down-regulated, mostly in association with retinal differentiation. Most of the transcripts could be verified at the mRNA level, and some of the proteins encoded were stainable in retinal sections and gels.
Conclusions:
These data suggest that visual experience shapes the postnatal retinal differentiation whereas visual deprivation induces changes at both the cellular and molecular levels within the retina.
Keywords: 417 amblyopia •
759 visual impairment: neuro-ophthalmological disease •
698 retinal development