摘要目的 观察玻璃体腔注射鼠神经生长因子(NGF)对早期糖尿病大鼠玻璃体中感光细胞间维生素A类结合蛋白(IRBP)含量的影响.方法 Sprague-Dawley雄性大鼠96只,随机分为正常对照组(A 组)及实验组,分别为24、72只.实验组采用链脲佐菌霉素(STZ)一次性腹腔注射制作糖尿病动物模型,再随机分为糖尿病阳性对照组(B组)、糖尿病玻璃体腔生理盐水注射组(C组)和糖尿病玻璃体腔鼠NGF注射组(D组),每组24只大鼠.A组及B组建模后不给予任何干预;C组注射生理盐水4μl,1次/周;D组注射0.5μg/μl的鼠NGF 4 μl,1次/周.注射后2、4、6、8周,采用酶联免疫吸附测定(ELISA)法检测大鼠玻璃体中IRBP含量;作石蜡切片行苏木精-伊红(HE)染色,光学显微镜观察视网膜结构;作超微切片,透射电子显微镜观察视网膜超微结构.结果 注射后2周,A、B、C、D组大鼠玻璃体中IRBP含量比较,差异无统计学意义(F=2.833,P=0.052).注射后4、6、8周,A、B、C、D组大鼠玻璃体中IRBP含量比较,差异均有统计学意义(F=22.252,108.459,105.726;P值均=0.000).A组组内注射后不同时间点大鼠玻璃体中IRBP含量比较,差异无统计学意义(F=1.462,P=0.241);B、C、D组组内注射后不同时间点大鼠玻璃体中IRBP含量比较,差异均有统计学意义(F=150.98,63.519,64.604;P值均=0.000).光学显微镜观察发现,A组大鼠视网膜各层组织层次清楚,排列整齐.注射后2、4周,B、C、D组大鼠视网膜结构较A组无明显改变.注射后8周,B、C、D组大鼠视网膜厚度变薄.透射电子显微镜观察发现,A组大鼠视细胞外节膜盘结构清晰,排列规则.注射后2周,B、C、D组大鼠视细胞外节膜盘结构清晰,排列规则整齐.注射后4周,B、C、D组大鼠视细胞外节膜盘局部模糊不清,间隙略有扩大.注射后8周,B、C组大鼠视细胞外节膜盘局部模糊不清,间隙扩大,部分出现溶解、断裂;D组大鼠视细胞外节膜盘局部模糊不清,间隙扩大,未见明显溶解断裂.结论 玻璃体腔注射鼠NGF可以有效稳定糖尿病大鼠早期玻璃体中IRBP的含量.

abstractsObjective To observe the effect of intravitreal injection of mouse nerve growth factor (NGF)on interphotoreceptor retinoid-binding protein(IRBP)in the vitreous of diabetic rats at early stages.Methods Ninety-six male Sprague Dawley(SD)rats were divided into control group(group A,24 rats)and experimental group(72 rats).The rats in experimental group were induced with streptozotocin injection for diabetic retinopathy model,and then randomly divided into positive control group(group B),normal saline group(group C)and NGF group(group D),24 rats in each group.The rats in the group A and B were not intervened.The rats were received intravitreal injection with 4μl normal saline(group C)or 4 μl(0.5 μg/μ1)NGF(group D).At 2,4,6 and 8 weeks after injection,IRBP levels were detected bv enzvmelinked immunosorbent assay(ELISA);hematoxylin-eosin(HE)staining and light microscope were used to observe the morphological changes of the retina;transmission electron microscope was used to observe the retinal uhrastructure.Results At 2 weeks after injection,there was no significant difference in IRBP expression between group A,B,C and D(F=2.833,P=0.052).At 4,6,8 weeks after injection,the differences of IRBP expression between group A,B,C and D were significant(F=22.252,108.459,105.726;P=0.000).At different time points after injection,there was no significant difference in IRBP expression of group A(F=1.462,P=0.241),but there were significant differences in IRBP expression of group B.C and D(F=150.98,63.519,64.604;P=0.000).Light microscope found that the retinal structure was clear in group A and in group B,C,D at 2,4 weeks after injection;the retinal thickness were thinner in group B,C,D at 8 weeks after injection.Transmission electron microscope displayed that the structure of rod outer segments was clear in group A and in group B,C,D at 2 weeks after injection;partly unclear structure of rod outer segments and slightly enlarged gap were observed in group B,C,D at 4,8Weeks after injection.Conclusion Intravitreal injection with NGF can stabilize the IRBP expression in the vitreous of diabetic rats at early stages effectively.