葛根素对大鼠视网膜缺血再灌注损伤的保护作用

目的观察葛根素(puerarin)对大鼠视网膜缺血再灌注的保护作用及机制。方法成年Wistar大鼠随机分成对照组、缺血再灌注未治疗组、缺血再灌注葛根素治疗组。采用前房灌注液体形成高眼压而建立RIR模型。治疗组在缺血前30min给予大鼠腹腔内注射葛根素。缺血60min后恢复血流。光镜观察各组视网膜内层厚度以及浸润入视网膜的中性粒细胞数目、神经节细胞数变化;免疫组化法检测Caspase-3蛋白在各组视网膜中的表达。结果葛根素治疗组再灌注6h以后各时间段视网膜内层厚度均较未治疗组视网膜缺血再灌注厚,早期视网膜内层水肿增厚,晚期视网膜神经节细胞数目减少及视神经纤维层萎缩变薄,神经节细胞数目多于未治疗组,而视网膜中的中性粒细胞数目少于未治疗组;Caspase-3蛋白于再灌注后24h达到高峰,但各时间段治疗组表达强度均较未治疗组明显减弱。结论葛根素对视网膜缺血再灌注损伤有治疗作用,抑制缺血再灌注损伤后的炎症反应和Caspase-3蛋白的表达是其可能的保护机制。

The protective effect of puerarin to retina ischemia-reperfusion injure

Objective To study the protective effect and mechanisms of puerarin to retina ischemia-reperfusion (RIR) injure. Method Adult wistar in spite of male or female rates were randomly assigned to 3 groups:control,ischemia-reperfusion,ischemia-referfusion Pur group.The modle of IRI were accomplished in Wistar rates by increasing the intraocular pressure to 14.33Kp for 1 hour via cannulation into anterior chamber.rats were treated with 0.5g/kg puerarin before operation by intrapertoneal injected. Retinal histological changes were observes,the number of RGCs and the leukocyte infiltrating in retinal were counted,and image analysis system was usesd to detect the thickness of inner retinal layer.The expression of Caspase-3 was assessed by immunohistlchemistry. Results Every stage after 6 hours of RIR, The inner layers of retina of the treated was thicker than the untreated. while at the later stage the decrease of RGCs number and the atrophy and thinning of nerve fiber layer were the main changer.During the early period of reperfusion, the edema of retina was reduced in treatment group than the ischemia. The number of RGCs of treatment group was more and the number of leukocyte was less than the untreated.The expression of Caspase-3 began to increase at 6th hour and reached the peak at 24th.With the reperfusion time prolonged,it began to deceased.The expression of the treated group was relatively obvious less than the untreated. Conclusion Puerarin has therapeutical effect to retinal ischemia-reperfusion injure.The possible protective mechanism is that puerarin can downregulate Caspase-3 expression and decrease inflammatory reaction induced by retinal ischemia-reperfusion.