CAJ | 학술논문

观察N-甲基-N亚硝脲(MNU)诱导的大鼠视网膜损伤对光感受器间维生素A类结合蛋白(IRBP)和恢复蛋白(recoverin)在视网膜中的表达变化.方法雌性Sprague-Dawley大鼠30只随机分为正常对照组和MNU处理1、3、7、10d组,每组均为6只大鼠.不同时间MNU处理组大鼠按体重40 mg/kg给予一次性腹腔注射MNU;正常对照组大鼠腹腔注射生理盐水5 ml/kg.逆转录-聚合酶链反应(RT-PCR)和免疫荧光检测各组大鼠视网膜中IRBP和恢复蛋白的mRNA及蛋白表达.结果 RT-PCR检测结果显示,与正常对照组比较,不同时间MNU处理组IRBP的mRNA表达水平随MNU作用时间增加而逐渐降低,差异均有统计学意义(P＜0.01)；恢复蛋白的mRNA表达水平随MNU作用时间增加而逐渐升高.MNU处理1d组恢复蛋白的mRNA表达水平与正常对照组比较,差异无统计学意义(P＞0.05)；MNU处理组3、7、10d组恢复蛋白的mRNA表达水平与正常对照组比较,差异均有统计学意义(P＜0.05).免疫荧光显微镜观察结果显示,正常对照组大鼠视网膜IRBP主要表达在光感受器细胞内、外节；不同时间MNU处理组IRBP在视网膜各层均有表达并随MNU作用时间增加而逐渐降低.恢复蛋白阳性标记物主要见于视网膜内核层、内丛状层及节细胞层,随MNU作用时间增加恢复蛋白的表达逐渐增强.结论MNU可降低IRBP的表达,但增加恢复蛋白的表达.
관찰N-갑기-N아초뇨(MNU)유도적대서시망막손상대광감수기간유생소A류결합단백(IRBP)화회복단백(recoverin)재시망막중적표체변화.방법자성Sprague-Dawley대서30지수궤분위정상대조조화MNU처리1、3、7、10d조,매조균위6지대서.불동시간MNU처리조대서안체중40 mg/kg급여일차성복강주사MNU;정상대조조대서복강주사생리염수5 ml/kg.역전록-취합매련반응(RT-PCR)화면역형광검측각조대서시망막중IRBP화회복단백적mRNA급단백표체.결과 RT-PCR검측결과현시,여정상대조조비교,불동시간MNU처리조IRBP적mRNA표체수평수MNU작용시간증가이축점강저,차이균유통계학의의(P＜0.01)；회복단백적mRNA표체수평수MNU작용시간증가이축점승고.MNU처리1d조회복단백적mRNA표체수평여정상대조조비교,차이무통계학의의(P＞0.05)；MNU처리조3、7、10d조회복단백적mRNA표체수평여정상대조조비교,차이균유통계학의의(P＜0.05).면역형광현미경관찰결과현시,정상대조조대서시망막IRBP주요표체재광감수기세포내、외절；불동시간MNU처리조IRBP재시망막각층균유표체병수MNU작용시간증가이축점강저.회복단백양성표기물주요견우시망막내핵층、내총상층급절세포층,수MNU작용시간증가회복단백적표체축점증강.결론MNU가강저IRBP적표체,단증가회복단백적표체.
Objective To investigate the effect of N-methyl-N-nitrosourea (MNU) on expressions of interphotoreceptor retinoid-binding protein (IRBP) and recoverin in rat retinal.Methods Thirty female Sprague-Dawley (SD) rats were randomly divided into five groups,including normal control group,and MNU treatment one day,three days,seven days and 10 days groups,each group had six rats.Rats in MNU-treatment groups received a single intraperitoneal injection of 40 mg /kg MNU,while rats in the normal control group received intraperitoneal injection of saline 5 ml/kg.Reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescence were used to detect the retinal expression of IRBP and recoverin.Results RT-PCR results indicated that retinal IRBP levels decreased after MNU injection compared with normal control (P＜0.01),while recoverin levels increased (one day:P＞0.05; three days:P＜0.05; seven days:P＜0.5; 10 days:P＜0.05).Immunofluorescence assays demonstrated that normally IRBP protein is mainly in the inner and outer segments of photoreceptors.After MNU treatment,IRBP protein was detected in all retinal layers but much faint.Recoverin was expressed in the inner nuclear layer,inner plexiform layer and ganglion cell layer,and its expression was increased after MNU injection.Conclusion MNU suppresses IRBP expression and promotes recoverin expression in rat retina.