Nogo受体(N-20)在大鼠视神经损伤后视网膜的表达

观察Nogo受体(NgR)在Wistar大鼠视神经(ON)损伤后视网膜各层的表达变化及分布规律,为Nogo蛋白抑制中枢神经再生的理论提供形态学依据。本实验各组动物均采用眶内眼球后2 mm ON切断术,术后动物分别存活3 d和7 d后取视网膜固定、冰冻后做水平切片,用免疫组织化学的方法观察NgR的表达情况。结果显示:NgR在正常对照组视网膜内3层有表达;在切断ON后实验各组有强烈表达;各组在损伤ON和移植神经组织后存活3 d时也有强烈表达,至7 d时表达有所下降。以上结果表明:NgR在大鼠ON损伤后视网膜的表达位于节细胞层、神经纤维层和内网层;其表达程度与移植物的种类有关,并可随存活时间的延长而下降。

THE EXPRESSION OF Nogo RECEPTOR (N-20) IN THE RETINA OF RAT AFTER OPTIC NERVE INJURIES

To observe the distribution and the expression changes of Nogo receptor (N-20)-like immune ore activity (NgR-LI) in the retina of Wistar rats after the optic nerve injury, and provide morphological evidence for the theory of Nogo protein inhibition of the central nervous system (CNS) regeneration, optic nerve (ON) was cut at 2 mm behind of the eyeball in the experimental group rat in the present study. After a survival period of 3 d and 7 d, the retinas were removed, fixed, frozen, sectioned horizontally and immunostained with antibody against NgR. Then, the expression of NgR was observed under microscopy. The present results showed that NgR-LI was expressed at various degree at inner 3 layers of the retina in normal control group and the strongest expression of NgR-LI was detected in the ON injured group. In the transplantation of nerve tissue groups after ON was injured, the expression of NgR-LI was still very strong on 3 d post-axotomy and decreased on 7 d post-axotomy. The above results demonstrate that NgR-LI is expressed in the ganglionic cell layer, the layer of optic nerve fiber and the inner plexiform layer, and the level of expression of NgR-LI in the retina is correlated with the kinds of implant and decreases as the survival time prolongs.