中药复方VIS抑制急性高眼压大鼠视网膜神经节细胞凋亡  

VIS,a compound of Chinese herb extracts, inhibits retinal ganglion cell apoptosis in a rat acute intraocular hypertension model

作　　者：尹朔 刘立夏[2] 冀璐[1] 王中峰[3] 路雪婧[1] 

机构地区：[1]成都中医药大学,四川省中医药眼病防治与视功能保护重点实验室,四川成都610072 [2]河南护理职业学院,河南安阳455001 [3]复旦大学脑科学研究院,神经生物学研究所,中国上海200032

出　　处：《中医眼耳鼻喉杂志》2015年第2期85-91,共7页Journal of Chinese Ophthalmology and Otorhinolaryngology

基　　金：国家重大科技专项（2009ZX09103-369）;教育部科学技术研究重点项目（2010188）;四川省学术技术带头人培养基金

摘　　要：目的研究中药复方VIS的不同配比对急性高眼压大鼠视网膜凋亡相关分子Bcl-2／Bax表达的影响，以及其组成成分DSX对视网膜神经节细胞外向钾电流的调控，探讨其视神经保护的可能机制。方法利用前房灌注生理盐水的方法急性升高大鼠眼内压，接着使用不同配比比例的VIS及LG、DSX灌胃7d，利用免疫组化方法检测凋亡相关基因的表达，再选取其组成成分DSX利用全细胞膜片钳技术观察其对急性分离的正常大鼠视网膜神经节细胞的电压门控外向钾电流的作用。将细胞膜电位钳制在-70mV，然后给予一系列400ms的去极化脉冲，以10mV的递增使细胞去极化到＋20mV，从而诱导出外向钾电流。结果前房急性灌注生理盐水7d造成视网膜凋亡相关基因Bcl-2／Bax比值的下调，不同配比的VIS呈不同程度地下调促凋亡基因Bax，促进凋亡抑制基因Bcl-2的表达，因而提高Bcl-2／Bax比值。同时胞外施加的DSX对大鼠RGC的外向钾电流的电流幅度呈电压依赖性压抑。结论急性眼内压升高引起视网膜内在凋亡途径的启动，中药复方VIS能够有效地抑制神经节细胞的凋亡，其组成成分DSX可逆地压抑大鼠视网膜神经节细胞外向钾电流，这可能是灯盏细辛对高眼压引起的视野丢失、视网膜神经节细胞损伤保护作用的机制之一。Objective To investigate the effect of VIS,a Chinese herbal compound,on the expression of Bcl-2/Bax, two apoptosis related proteins,in rat retina with acute ocular hypertension, and the effect of the component DSX on RGC outward K^＋ current, thereby exploring the possible mechanisms of DSX on optic nerve protection. Methods Rat acute ocular hypertension model was reproduced by anterior chamber perfusion with normal saline for 60 minutes. VIS was administered by a method of gavage for 7 days consecutively. Expression of Bcl-2/Bax was examined by using immunohistochemistry method. Outward potassium channel currents were recorded by using whole-cell patch-clamp techniques on acutely isolated RGCs. Outward K^＋ currents were induced by a series of depolarizing voltage pulses from a holding potential of -70 mV to ＋20 mV in an increment of 10 mV. Results The ratio Bcl-2/Bax was decreased at 7 d after elevation of intraocular pressure, which was reversed by VIS. Extracellular application of DSX significantly and voltage-dependently suppressed outward K^＋ current amplitudes of the retinal ganglion cells. Furthermore, DSX reversibly and dose-dependently inhibited the amplitude of outward K^＋ currents. Conclusion These results suggest that acute elevation of intraocular pressure triggers retinal intrinsic apoptotic pathway,and the traditional Chinese medicine compound VIS can effectively inhibit apoptosis of retinal ganglion cells. DSX reversibly and dose-dependently suppress outward potassium channel currents in rat retinal ganglion cells,which may be one of the possible mechanisms underlying VIS prevents vision loss and retinal ganglion cell damage caused by glaucoma.

关 键 词：急性高眼压 中药复方VIS 灯盏细辛DSX 视网膜神经节细胞 BCL-2/BAX 钾 通道 大鼠 

分 类 号：R774[医药卫生—眼科]