核转录因子-κB在氧诱导血管增殖性视网膜病变小鼠中的表达

Expression of nuclear factor-kappa B in mice with oxygen-induced proliferative retinopathy

目的探讨氧诱导血管增殖性视网膜病变小鼠视网膜中核转录因子(nuclear factor,NF)-κB蛋白的表达变化及意义。方法 72只出生后7 d的C57BL/6J小鼠随机分为实验组(36只)和对照组(36只),实验组与母鼠一起放入氧气含量为体积分数75%的饲养箱中饲养,出生后12 d回到正常大气环境中;对照组小鼠始终在正常大气环境中饲养。分别于出生后12 d、14 d、17 d时处死小鼠,荧光素灌注后行视网膜铺片观察血管分布及形态,Western blot法检测视网膜中血管内皮生长因子(vascular endothelial growth factor,VEGF)的蛋白表达变化,免疫组织化学染色检测眼球中NF-κB的表达变化。结果视网膜铺片检查结果可见,实验组小鼠出生后14 d开始出现视网膜新生血管,面积为每眼(0.06±0.12)mm2;生后17 d达到高峰,面积为每眼(1.79±0.02)mm2(χ2=20.112,P<0.01)。Western blot检测结果显示,实验组VEGF表达不断增强,在生后17 d时表达达到高峰,为0.83±0.05。免疫组织化学染色结果显示,实验组生后12 d NF-κB阳性细胞计数为(12.32±1.04)个·mm-2,14 d时为(19.16±1.02)个·mm-2,生后17 d阳性表达较12 d和14 d时均高,为(28.60±0.52)个·mm-2(χ2=13.102,P<0.05;χ2=20.132,P<0.01)。结论 NF-κB在氧诱导血管增殖性视网膜病变小鼠视网膜中表达明显升高,其趋势与VEGF的变化相同,NF-κB参与了缺氧状态下视网膜新生血管形成的调控过程。

Objective To investigate the expression of nuclear factor-kappa B （NF-κB） in mice with oxygen-induced proliferative retinopathy and its significance. Methods Seventy-two 7-day-old C57/BL6 mice were randomly divided into model group （36 mice）and control group （36 mice）. The mice in model group were raised in a box full of 75% 02 and then under the normal atmosphere condition on the 12th postnatal day. The mice in control group were raised under the normal circumstance all the time. On the 12th,14th,17th postnatal day after birth,4 mice in each group at each time point were observed under the fluorescent microscope after fluorescein perfusion, and the expression of vascular endothelial growth factor （VEGF）proteins in 5 mice of each group were detected by Western blot. The expressions of NF-κB of 3 mice in each group were detected by immunohistochemistry. Results Retina flat mounting showed that on the 14th postnatal day,the neovascularization in model group appeared,the area was （0.06 ±0.12）Mm2 in each eye,and reached the peak on the 17th postnatal day,the area was （1.79 ±0.02 ）mm2 in each eye, the difference was significant （X2 = 20. 112, P 〈 0.01 ）. Western-blot showed that in model group ,the expression of VEGF increased and reached the peak on the 17th postnatal day,which was 0.83 ＋0.05. No NF-κB positive cells were observed in the retina of normal mice. Immunohistochemistry showed that the positive cells of NF-κB on the 12th,14th postnatal day was （ 12.32 ± 1.04）mm^-2 and （19.16 ± 1.02）mm^-2, and reached the peak on the 17th postnatal day, which was （28.60± 0.52）mm^-2, there were statistical differences compared with the 12th, 14th postnatal day （X2 = 13. 102 ,P 〈 0.05 ;X2 = 20.132 ,P 〈 0.01 ）. Coneluslon The expression of NF-κB in retinal tissue obviously increases in mice with oxygen-induced proliferative retinopathy with same tendency as VEGF changes, which indicates that the expression of NF-κB is correlated with retinal neovascularization.