Variation In ONL Thickness And Expression In NF-κB After Retinal Optical Damage Of Rats And The Influence Of PDTC On Them

[Objectives]Observation on variation in ONL thickness and expression in NF-κB after retinal optical damage of rats, the influence of PDTC on ONL thickness and expression in NF-κB, investigating the mechanism of retinal optical damage as well as its prevention and therapy.[Methods]1.45SD rats were randomly divided into three groups involving5in blank control group,20in illuminated group and20in PDTC group. All rats were feed for1week under indoor natural circulated light and white fluorescent lamp which is12h for brightness and12h for darkness.2. All rats were feed for24h under absolute darkness, while20h in the period rats in PDTC group under low light were standard intraperitoneal injection of PDTC solution of1mg/ml according to50mg/kg, blank control and illuminated group were no processing.3. After dark adaptation, rats in PDTC group under low light were dilated each pupil using tropicamide eye drops and placed into optical damage case which irradiated for24h by green light then feed under low light.4. Rats in PDTC group were standard intraperitoneal injection of PDTC solution of1mg/ml according to50mg/kg for each day. Rats in blank control were put to death after dark adaptation, rats in illuminated group as well as in PDTC group were put to death randomly for2during the time point in1d,3d,7d and17d, removing eyeballs for pathological section. 5.The sections were conducted by HE staining and NF-κB(P65) immunohis-tochemical staining. Measurement on ONL thickness from images of HE staining and gray value from graphs of NF-κB(P65) immunohistochemical staining via image analysis software named Image-Pro plus6.0. and analyzed relevant data through statistical software of SPSS17.0.[Results]1. HE staining:retina in blank control were normal morphology and distinct in the structure of each layer; retina in illuminated group as well as in PDTC group both appeared the phenomenon of the reduction in number of nuclei, irregular nuclei and disordered arrangement after irradiated for Id, and the thickness of ONL reduced, however there was no significant difference between the two groups; the damage further increased until irradiated for7d, during such period the reduced level of illuminated group on the thickness of ONL was higher than PDTC group; during irradiated for7d to14d. the retinal damage in the two groups were leveling out, but the thickness of ONL in PDTC group was still higher than in illuminated group.2. NF-κB(P65) immunohisto-chemical staining:there were only a few NF-κB expressed in blank control and distributed mainly on the inner nuclear layer in nuclei; expression of NF-κB was sharply increased in illuminated group as well as in PDTC group after irradiated for ld. mostly distributed on the inner nuclear layer, outer nuclear layer and ganglion cell layer of nuclei and all around, expression of NF-κB in the two time point in the two groups was no distinct difference:expression of NF-κB in the two groups both apparently decreased since subsequent each time point, but expression of NF-κB in each time point in PDTC groups were all fewer than in illuminated groups, and the rate of descent on expression of NF-κB in PDTC groups were faster than in illuminated groups, until irradiated for14d. expression of NF-κB in PDTC groups were approached to blank control.[Conclusions]1.Tissue observation demonstrated that the model of retinal optical damage of rats o f green fluorescent irradiation could be successfully established.2.Retinal ONL thickness decreased after irradiation and PDTC could protect retinal ONL to some extent;3. Expression of NF-κB of retina increased after irradiation and PDTC could reduce the expression of NF-κB in retina.4.NF-κB may take part in the process of optical damage of retina and PDTC could protect retina.