Mo M.-S.,Xian Jiaotong University |
Mo M.-S.,China Key Laboratory of Environment and Genes Related to Diseases |
Li H.-B.,Xian Jiaotong University |
Wang B.-Y.,Xian Jiaotong University |
And 6 more authors.
Journal of Xi'an Jiaotong University (Medical Sciences) | Year: 2012
Objective: To compare the sensitivity of light damage of retinas among SD, E3 and DA1U rats and provide experiment data for facilitating the model construction of light damage in retina and further study of the correlated mechanism between light damage and distribution of pigments in retina. Methods: Electroretinogram (ERG) and HE staining were used to detect the functional and morphological changes in adult SD, E3 and DA1U rats before and after light damage. TUNEL staining was used to observe the distribution and the number of apoptotic retinal cells. Results: In normal conditions, retinal pigment epithelium layer and choroid layer of SD rats and retinal pigment epithelium layer of E3 rats did not contain pigments, while choroid layer of E3 rats and retinal pigment epithelium layer and choroid layer of DA1U rats had brown granules. HE staining results revealed that these rat strains did not differ significantly in the thickness of outer nuclear layer (ONL) in normal conditions. After light damage, the cell layers of SD rat retinas were severely decreased. ERG results showed that in normal status, there were significant differences among different rat strains in the amplitude of b-wave of rod-ERG. SD and E3 rats differed significantly in the amplitude of both a-wave and b-wave of max-ERG. However, after light damage, the amplitude of a-wave and b-wave of max-ERG in E3 and DA1U rats decreased significantly as compared with SD rats. TUNEL staining showed that compared with SD rats, E3 and DA1U rats had the significantly decreased scope and number of apoptotic cells in retinal ONL and inner nuclear layer (INL). Conclusion: Retinal pigment distribution and sensitivity of light damage differ among SD, E3 and DA1U rats. The pigments in the retinal pigment epithelium layer and the choroid layer may play an important role in protecting retinas from light damage.