枸杞多糖对大鼠视网膜光损伤的形态及功能的影响

Effects of lycium barbarum polysaccharide on retinal morphometry and function of retinal photic injury in rats

目的探讨枸杞多糖(LBP)对视网膜光损伤形态及功能的影响。设计实验性对照研究。研究对象SD大鼠60只,每组10只。方法建立视网膜光损伤模型,未治疗组于光照前、光照后1天、6天及14天行暗视闪光视网膜电图(ERG)检查,检查完后取每组大鼠眼球上方中央部视网膜行组织病理学检查。于光照前24h及0.5h腹腔注射LBP和生理盐水分别作为LBP治疗组及阳性对照组,光照后1天行暗视闪光ERG,后取眼球上方中央部视网膜标本行组织病理学检查。主要指标ERG b波振幅,视网膜形态学。结果在未治疗组,光照后各时间点标本与正常组对比ERG b波振幅明显下降,第1天降至29.97%,而第6天、第14天b波振幅无继续下降。第1天标本组织形态学显示其损伤最严重,第6天、第14天标本形态上则慢慢恢复。LBP治疗组,ERG b波振幅较阳性对照组明显升高(P=0.005),视网膜形态学未见明显凋亡改变。结论LBP对大鼠视网膜光损伤的功能和形态损害具有防护作用。

Objective To investigate the functional protective effect of lycium barbarum polysaccharide （LBP） against light-induced retinal degeneration. Design experimental studies. Participants sixty SD rats were divided randomly into 6 groups. Methods Sprague-Dawley rats were exposed for 24 hours to 2000-lux cool white fluorescent light after treatment with LBP. Scotopic flash electroretinogram （ERG） were recorded before and on day D1, D6 and D14 after light exposure. The b-wave amplitude was statistic. In addition, rats from each group were killed for retinal morphometric analyses. Main outcome Measure The amplitudes of b-wave of scotopic flash ERG, the histopathological changes. Results In the untreated group, light exposure caused collapse of the b-wave sensitivity curves. Bmax was reduced by 29.97% at D 1 without subsequent recovery. Histopathology of the temporal superior central retinas of rats showed outer segment disorganization and shortening, the inner segments swelled and vacuolated, the outer nuclear layer thicknesses decreased markedly with subsequent recovery. In the treated groups, light exposure had a weaker effect on sensitivity curves. The values of b-wave amplitude were significantly increased than those in the exposed-untreated group （P=0.005）. Retinal morphometry was preserved. Conclusion LBP afford functional protection against light-induced retinal damage. （Ophthalmol CHN, 2009, 18： 229-233）