视网膜变性对RCS-P^+大鼠γ-氨基丁酸及其合成酶谷氨酸脱羧酶65表达的影响  

Effect of retinal degeneration on expression of γ-aminobutyric acid and glutamic acid decarboxylase 65 in RCS-P^+ rats

作　　者：何建荣[1] 陈丽峰[1] 李瑶琛[1] 

机构地区：[1]第三军医大学西南医院全军眼科中心,重庆400038

出　　处：《第三军医大学学报》2013年第5期390-393,共4页Journal of Third Military Medical University

基　　金：国家自然科学基金面上项目(81271021);国家自然科学基金青年科学基金(30800213)~~

摘　　要：目的观察视网膜变性过程中γ-氨基丁酸(γ-amino butyric acid,GABA)及合成酶谷氨酸脱羧酶65(glutamicacid decarboxylase 65,GAD65)的表达变化。方法选择出生后15、30、60、90 d的RCS-P+和同年龄的RCS-rdy+-P+大鼠,采用免疫荧光(IF)和免疫印迹法(Western blot)观察两种大鼠出生后15、30、60、90 d GABA和GAD65的表达差异。结果视网膜中GABA和GAD65主要表达于内核层、内从状层和节细胞层。随着天龄的增加,RCS-rdy+-P+大鼠中GABA阳性细胞逐渐减少。RCS-P+变性鼠在出生后15～60 d GABA阳性细胞随天龄增加逐渐减少,在出生后60～90 d(即视网膜变性中晚期)GABA阳性细胞大量增加,GABA表达明显高于RCS-rdy+-P+大鼠(P<0.05)。不同年龄RCS-rdy+-P+大鼠其GAD65表达恒定,发育对GAD65表达无明显影响;与同年龄RCS-rdy+-P+大鼠相比,30 d RCS-P+大鼠GAD65表达略有增加(P<0.05),90 d时大量增加(P<0.01),其表达随病变发展明显升高。结论在视网膜色素变性过程中,GABA、GAD65在视网膜内层的表达均有显著的升高,提示输入剥夺后GABA能无长突细胞未见损伤,其活性甚至略有增高。Objective To determine the the expression of γ-aminobutyric acid （GABA） and its synthetic enzyme, glutamic acid decarboxylase 65 （GAD65）, during retinal degeneration. Methods Pigmented Royal College of Surgeon rats （RCS-P＋） and RCS-rdy＋-P＋ rats at age of postnatal 15, 30, 60 and 90 d were selected to study the expression changes of GABA and GAD65 at different time points in retinas by immunofluorescence and western blotting analysis. Results GABA and GAD65 were mainly expressed in the inner nuclear layers （INL）, inner plexiform layers （IPL） and ganglion cell layer （GCL）. The number of GABA positive cells in RCS-rdy＋-P＋ rats’ retinas gradually reduced with the age. The number of GABA positive cells in RCS-P＋ was reduced from 15 d to 60 d. However, the number of GABA positive cells was significantly increased after 60 d when compared with RCS-rdy＋-P＋ rats’ retinas（P〈0.05）. Furthermore, the expression of GAD65 was constant during the retinal development in RCS-rdy＋-P＋ rats, and the development did not affect the expression level of GAD65. Compared with the age-matched RCS-rdy＋-P＋ rats, the expression of GAD65 was increased with the retinal degeneration. The expression of GAD65 was increased at 30 d in RCS-P＋ rats（P〈0.05）, and its expression was significantly increased at 90 d（P〈0.01）. Conclusion During retinal degeneration, the expression of GABA is consistent with GAD65, and both of their expression is increased significantly. The deprivation of input has little effect on the activity of GABAergic amacrine cells, even higher than that of control retinas.

关 键 词：视网膜变性 Γ-氨基丁酸 GAD65 

分 类 号：R341.7[医药卫生—基础医学] R394.1