倍他洛尔对实验性视网膜缺血再灌注损伤后视神经的保护作用  

Protective effect of betaxolol on optic nerves after experimental retinal ischemia-reperfusion injury

作　　者：荣华[1] 艾明[1] 邢怡桥[1] 陈长征[1] 易莲芳[1] 杨安怀[1] 

机构地区：[1]武汉大学人民医院眼科

出　　处：《中华眼底病杂志》2005年第4期249-252,共4页Chinese Journal of Ocular Fundus Diseases

摘　　要：目的探讨倍他洛尔对实验性视网膜缺血再灌注损伤后视神经的保护作用及其可能的作用机制。方法采用升高眼内压的方法,制作大鼠实验性视网膜缺血再灌注损伤模型。将68只SD大鼠随机分为正常对照组(8只)、0.25%倍他洛尔治疗组(30只)和生理盐水对照组(30只)。其中后两组根据再灌注的不同时间各分为1、3、7d组,每组10只大鼠。治疗组鼠右眼滴入0.25%倍他洛尔眼药水,生理盐水对照组鼠右眼滴入生理盐水。观察治疗组和生理盐水对照组及正常对照组鼠视网膜电图(ERG)b波振幅及光学显微镜、电子显微镜下视网膜结构变化;免疫组织化学法检测神经性一氧化氮合酶(nNOS)的表达,分光光度法测定丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性。结果从再灌注1d开始,生理盐水对照组ERG的b波振幅持续下降,病理组织损害逐渐加重,视网膜中nNOS阳性表达明显增多,MDA水平持续升高,SOD水平持续下降,其差异与正常对照组比较均有统计学意义(P<0.01);与生理盐水对照组相比,再灌注各时段倍他洛尔治疗组ERG的b波振幅明显恢复(P<0.01),病理组织损害明显减轻,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),其中nNOS阳性神经元与正常对照组的差异无统计学意义(P>0.05)。结论倍他洛尔可能通过减少细胞内Ca2+超载,抑制NO的产生和提高抗氧化能力,对大鼠实验性视网膜缺血再灌注损伤有一定的保护作用。Objective To investigate the protective effect and mechanism of betaxolol on optic nerves after experimental retinal ischemia-reperfused injury. Methods Retinal ischemia was induced in SD rats by increasing intraocular pressure through intracameral infusion. Sixty-eight rats were randomly divided into 3 groups: normal control (eight rats), 0.25% betaxolol treatment (thirty rats) and saline control group (thirty rats). The latter two groups were subdivided into group 1 day, 3 and 7 days after reperfusion, respectively, with 10 rats in each group. Betaxolol and normal saline was applied to the right eyes of the rats in the treatment group and to the ones in normal saline control group, respectively. The amplitude of b-wave of electron retinograph (ERG) was observed and the histological and ultrastructural changes were detected by light and electron microscopy. The expression of neural nitrogen oxide synthase (nNOS) was detected by immunohistochemistry. The content of malonyldialdehyde (MDA) and the superoxide dismutase (SOD) activity were measured by spectrophotometer. Results [WTBZ]Began from the first day after reperfusion, in saline control group, the amplitudes of ERG b-wave reduced continuously, the histopathological damages of retina were aggravating, 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 saline control group, the amplitudes of b-wave of ERG in betaxolol treatment group after reperfusion got right obviously(P<0.01), with alleviated histopathological damages, decreased nNOS positive neurons(P<0.01), decreased MDA content(P<0.01), and increased SOD activity (P<0.01), in which no statistical significance of nNOS positive neurons was found between the treatment group and normal control group (P>0.01). Conclusion Betaxolol, by reducing intracellular overfreight of Ca^(2+),inhibiting production of NO and elevating the ability of anti-oxidation in rat retina, can protect retin

关 键 词：倍他洛尔 药物作用 视网膜 缺血再灌注损伤 眼内压 

分 类 号：R774.1[医药卫生—眼科] R453.9[医药卫生—临床医学]