小鼠上丘Rap1B表达的发育性变化及关键期单眼形觉剥夺对其的影响

The developmental changes in the expression of Rap1B and the effect of monocular form deprivation during the critical period on its expression in the mouse superior colliculus

目的探讨小鼠上丘Rap1B表达的发育性变化以及视觉发育关键期单眼形觉剥夺(MD)对其表达的影响。方法SPF级健康雄性C57BL/6J小鼠45只为实验对象。实验一:小鼠上丘Rap1B表达的发育性变化。该实验小鼠分为3组,即关键期前组[生后18 d(P18)小鼠]、关键期组(P32小鼠)和成年组(P60小鼠),采用qPCR和Western blot检测各组小鼠左右两侧上丘中Rap1B基因及蛋白的表达量。实验二:MD对上丘Rap1B基因及蛋白表达的影响。该实验小鼠分为2组:右眼MD组(小鼠P28时右眼建立MD模型,至P32时行检测)与NC组(正常对照组,P32小鼠),采用qPCR和Western blot检测各组小鼠左右两侧上丘中Rap1B基因及蛋白的表达。结果关键期前组小鼠左右两侧上丘中Rap1B基因和蛋白表达量均较低;与关键期前组相比,关键期组小鼠Rap1B基因及蛋白表达量均显著增高(均为P<0.05);与关键期组相比,成年组小鼠Rap1B基因和蛋白表达量均显著降低(均为P<0.05)。与NC组相比,右眼MD组小鼠左侧上丘Rap1B基因和蛋白表达量均显著增高(均为P<0.05),而右侧上丘Rap1B基因和蛋白表达量均显著降低(均为P<0.05)。结论小鼠上丘中Rap1B基因表达的发育性变化趋势与视觉发育关键期相一致,Rap1B可能参与了关键期MD对上丘发育的调控。

Objective To explore the developmental changes in the expression of Rap1B and the effect of monocular form deprivation(MD)during the critical period of visual development on the expression of Rap1B in the mouse superior colliculus(SC).Methods Forty-five SPF-grade healthy male C57BL/6J mice were used in this experimental study.Experiment 1:To study the developmental changes of Rap1B expression in the mouse SC,the experimental mice were divided into three groups:the pre-critical period group[postnatal day 18(P18)],the critical period group(P32),and the adult group(P60).The expression levels of Rap1B gene and protein in the left and right SC of mice in each group were detected by quantitative polymerase chain reaction(qPCR)and Western blot,respectively.Experiment 2:To study the effect of MD on the expression levels of Rap1B gene and protein in the SC,the experimental mice were divided into two groups:the right eye MD group(MD models of the right eyes were established at P28 and detected at P32)and the normal control group(NC group,P32).The expression levels of Rap1B gene and protein in the left and right SC of mice in each group were measured by qPCR and Western blot,respectively.Results The expression levels of Rap1B gene and protein were low in the left and right SC of mice in the pre-critical period group;compared with the pre-critical period group,the expression levels of Rap1B gene and protein in the critical period group significantly increased(both P<0.05);compared with the critical period group,the expression levels of Rap1B gene and protein in the adult group significantly decreased(both P<0.05).Mice in the right eye MD group showed significantly higher expression levels of Rap1B gene and protein in the left SC(both P<0.05),while significantly lower expression levels of Rap1B gene and protein in the right SC(both P<0.05)compared to mice in the NC group.Conclusion The developmental trend of Rap1B gene expression in the mouse SC is consistent with the critical period of visual development,and Rap1B may be involved in the regulatory effect of MD during the critical period on the development of SC.