Y27632对急性视网膜缺血再灌注大鼠视网膜组织形态学的影响

目的:研究Rho激酶抑制剂Y27632对视网膜缺血再灌注损伤大鼠视网膜组织形态学的影响。方法:实验研究。将60只SD大鼠随机分为4组,每组15只:正常对照组(正常组)、急性缺血再灌注损伤组(IRI组)、0.9%氯化钠溶液对照组(生理盐水组)、Y27632治疗组(Y27632组)。再灌注损伤后24h(10只)和168h(5只)处死各组动物,行HE染色、ADP酶染色检查,光镜下观察大鼠视网膜组织病理学变化及视网膜厚度变化。数据采用单因素方差分析。结果:正常组大鼠视网膜结构清晰,三层细胞结构排列整齐。IRI组于再灌注24h后视网膜厚度增加,内外丛状层组织疏松,视网膜节细胞、内外核层细胞水肿明显、排列紊乱,视网膜节细胞减少。168h后,视网膜水肿消退、厚度变薄、呈萎缩状,神经节细胞及内外核层细胞数量减少,在视网膜前和神经纤维层可见毛细血管。再灌注24h后,IRI组视网膜厚度较正常组增加(P=0.005),Y27632组视网膜厚度低于生理盐水组(P=0.032)。再灌注168h后,IRI组视网膜厚度低于正常组(P<0.001),Y27632组视网膜厚度较生理盐水组增加(P=0.025)。正常组大鼠视网膜血管自视乳头发出,向四周呈放射状均匀分布,毛细血管网结构清晰。再灌注24h后,IRI组视网膜血管管径变细,走行较僵直,分支减少,视乳头周围及中周部视网膜可见大片无灌注区,无灌注区周围可见新生血管芽渐成网状。Y27632组可见视乳头周围及中周部视网膜局部无灌注区形成,无灌注区周围可见新生血管。后极部4PD无灌注区面积明显小于IRI组及生理盐水组。结论:Y27632玻璃体腔注射可以减轻视网膜缺血再灌注早期的视网膜水肿,减少视网膜神经节细胞的凋亡,减少视网膜新生血管生成,减轻再灌注晚期的视网膜萎缩,具有视神经保护作用。

The Effect of Y27632 on Retinal Tissue Histomorphology in Rats with Acute Retinal Ischemia-Reperfusion

To study the effect of rho kinase inhibitor Y27632 on retinal histomorphology in rats with retinal ischemia-reperfusion injury. Methods: In this experimental study, sixty SD rats were randomly divided into 4 groups, 15 in each group: normal group, ischemia-reperfusion injury group (IRI group), saline group, and Y27632 group. Twenty-four hours (10 rats) and 168 hours (5 rats) after the induction of ischemiareperfusion, the rats were sacrificed and the retinas were stained with HE and ADP. Histopathological changein the retina was examined and the thickness of the retina was measured. Data were analyzed by one-way ANOVA. Results: The retinal structure was clear and the structure of the three layer cells was orderly in the normal group. In the IRI group, after 24 hours of reperfusion, retinal thickness increased, the inner and outer plexiform layers were loose, the retinal ganglion cells and the inner and outer nuclear layers showed evidence of edema and were disordered and the retinal ganglion cells were reduced. After 168 hours, retinal edema subsided, and thickness was reduced and atrophic. The number of ganglion cells and inner and outer nuclear cells decreased. Capillaries were seen in the anterior retina and nerve fiber layer. After 24 hours of reperfusion, the retinal thickness of the IRI group was greater than that of the nomal group (P=0.005), and the thickness of the Y27632 group was lower than that of the saline group (P=0.032). After 168 hours of reperfusion, the retinal thickness of the IRI group was lower than that of nomal group (P<0.001), and the thickness of the Y27632 group was higher than that of the saline group (P=0.025). In the norml group, the retinal blood vessels were distributed uniformly and radially around the papillae, and the structure of the capillary network was clear. After 24 hours of reperfusion, retinal vessels in the IRI group were thinner, more rigid and had less branching. Large non-perfusion areas were observed around the retina and arund the optic papilla, and neovascularization buds were gradually reticulated around the non-perfusion area. In the Y27632 group, there was a non-perfusion area around the optic papilla and the middle retina, and neovascularization was around the non-perfusion area. The area of the non-perfusion zone in 4PD of the posterior pole was significantly less than that in the IRI andsaline groups. Conclusions: Y27632 intravitreal injection can reduce retinal edema, apoptosis of retinal ganglion cells, retinal neovascularization and retinal atrophy in the early stage of retinal ischemia-reperfusion. It has a protective effect on the optic nerve.