TNF-α在大鼠视网膜缺血再灌注损伤中的表达及NAC对其表达的影响

Expression of TNF-α in retinal ischemia-reperfusion injury in rats and the effect of NAC on it

目的研究肿瘤坏死因子-α(tumornecrosisfactor-α,TNF-α)在大鼠视网膜缺血再灌注损伤中的表达及N-乙酰-L-半胱氨酸(N-acetylcysteine,NAC)对其表达的影响。方法结扎颈总动脉建立大鼠视网膜缺血再灌注模型,60只SD大鼠随机分为缺血再灌注组和缺血再灌注+NAC组。每组按再灌注后不同时间段分为1h、6h、12h、24h、48h、72h组,每组5只。以原位杂交法检测TNF-α的表达,每只大鼠处死前行视网膜电图(ERG)检测,并计算出左/右眼ERG的比值。结果缺血再灌注组在6h开始检测到TNF-α的表达,在24h表达最强,以后逐渐减弱。缺血再灌注+NAC组在再灌注6h未能检测到TNF-α的表达,在第12h有TNF-α的表达,24h表达最强,但低于缺血再灌注组(P<0·05)。缺血再灌注组在再灌注6h后各期ERG相对恢复率明显低于缺血再灌注+NAC组(P<0.05)。结论NAC可能通过抑制TNF-α在视网膜缺血再灌注损伤中的表达而起保护作用。

Objective To study the expression of tumor necrosis factor-α （TNF-α） in retinal ischemta-reperfusion injury in rats and the effect of Nacetylcysteine（NAC） on it. Methods The model of rat retina＇s ischemiareperfusion injury was employed by ligation the common carotidartery, sixty SD rats were derided into the ischemia-reperfusion group and the ischemiareperfusion with NAC treat group. Each group was devidod into 1hour,6 hours, 12 hours,24 hours,48 hours,72 hours small groups according to the reperfusion time, each small group has 5 rats. In situ hybridization technology was used to test the expression of TNF-α mRNA in different stages of different groups＇ retina. ERG test was empolyod in different groups and stages. The 1eft/right eye＇ s ERGa, b wave of ampultide ratio were used as the relative recovery ratio. Results TNF-αm RNA could be detected at 6 hours after reperfusion injuried in ischemia-reperfusion group, which reached the highest level at 24 hours. TNF-αm RNA could be detected at 12 hours after reperfusion injuriod in ischemia-reperfusion with NAC treat group, which reached the highest level at 24 hours, but its expression was lower than the same time of ischemia-reperfusion group. The relative ERG recovery ratio of ischemia-reperfusion group was lower than NAC group. Conclusion NAC may protect the retina through inhibiting the TNF-α expression in rat＇ s retina which injuried by ischemiareperfuslon.