原花青素对大鼠视网膜缺血再灌注损伤后视神经的保护作用

目的探讨原花青素对大鼠高眼压视网膜缺血再灌注损伤后视神经的保护作用。方法用眼内灌注法,前房灌注林格液制成实验性高眼压视网膜缺血再灌注损伤模型。将70只Wistar大鼠随机分为正常对照组(10只)、模型对照组(30只)和原花青素干预组(30只)。模型对照组和原花青素干预组根据再灌注的时间不同分为1、3和7 d组,每组各10只。各组于造模前5 d开始用药,原花青素干预组每天用原花青素混悬液300 mg.kg-1灌胃,正常对照组、模型对照组分别给予灌注等量蒸馏水,每日分2次给药。造模后各组仍继续按原方案给药。造模后分别在1、3、7 d脱颈处死大鼠,迅速摘除眼球取出视网膜。利用双抗体夹心酶联免疫吸附法检测各组大鼠视网膜中超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量、神经元型一氧化氮合酶(nNOS)的表达水平。结果再灌注1 d,模型对照组nNOS的表达水平开始增高,3 d达高峰,7 d后逐渐下降。再灌注各时间点,模型对照组视网膜内nNOS阳性表达明显增多,MDA含量持续升高,SOD活性持续下降,与正常对照组比较,差异有统计学意义(P<0.01)。各时段原花青素干预组与模型对照组比较,视网膜内nNOS阳性神经元明显减少(P<0.01),MDA含量降低(P<0.01),SOD活性升高(P<0.01);与正常对照组比较,差异无统计学意义(P>0.05)。结论原花青素可通过提高视网膜组织中SOD活性,降低MDA含量,减少视网膜组织中nNOS表达,对大鼠视网膜缺血再灌注损伤有一定的保护作用。

Protective effect of proanthocyanidin on optic nervers after experimental retinal ischemia-reperfusion injury in rats

Objective To investigate the protective effect and mechanism of proanthocyanidin on optic nervers after experimental retinal ischemia-reperfused injury in rats.Methods Retinal ischemia-reperfusion injury was induced in Wistar rats by increasing intraocular pressure through intracameral infusion.Seventy rats were randomly divided into three groups:normal control(ten rats),model control group(thirty rats) and proanthocyanidin treatment(thirty rats).The latter two groups were subdivided into 1 day,3 and 7 days groups after reperfusion according to the different reperfusion time,with 10 rats in each group.Every group was given medicine before 5 days.Rats in the proanthocyanidin treatment group were injected proanthocyanidins suspl 300 mg·kg-1·d-1 by lavage;rats in the normal control group and the modle control group were injected distilled water with same dose,two times a day.Every group all still were taken medicine on the original plan after making the model.On the 1st day,the 3rd day,the 7th day after making the model,the rates in every group were come off the neck and put to death,the eyeball were removaled quickly and the retina were taken out of the rats.The expressions of neural nitrogen oxide synthase(nNOS),the content of malonyldialdehyde(MDA) and the superoxide dismutase(SOD) activity were measured by enzyme linked immunosorbent assay in retinal of groups rats.Results In model control group,began from the first day after reperfusion,the expression of nNOS positive neurons were increased,and reached height in the third day,and went down gradually in the seventh day.In model control group,the expression of nNOS increased,MDA level increased and SOD level decreased persistently,which significantly differed from the normal control group(P<0.01).In contrast to the model control group,the expression of nNOS positive neurons were decreased(P<0.01),MDA level decreased(P<0.01) and SOD level increased(P<0.01) in proanthocyanidin treatment group.No statistical significance was found between the proanthocyanidin treatment group and the normal control group(P>0.05).Conclusion Proanthocyanidin can protect experimental retinal from ischemia-reperfused injury by increasing SOD activity,decreasing the content of MDA and the expression of nNOS in rat′s retina.