不同波长人工发光二极管光照对大鼠视网膜的影响

目的　探讨红、绿、蓝、白四种不同波长人工发光二极管(LED)光照对大鼠视网膜的影响。方法　45只3周龄SD大鼠作为实验动物,分为空白对照组,以及1000 lux和2000 lux照度下的红光照射组、绿光照射组、蓝光照射组、白光照射组,每组各5只。空白对照组大鼠自然光线下饲养1个月,不同光照组采用相应波长LED进行光照,每天照射10 min,连续1个月。取各组大鼠左眼视网膜行TUNEL染色观察细胞凋亡情况,取各组大鼠右眼视网膜行Western blot检测视网膜中PARP和GFAP的蛋白相对表达量。结果　照度1000 lux时,红光照射组、绿光照射组、蓝光照射组、白光照射组大鼠视网膜TUNEL染色均未见明显的细胞核阳性染色;Western blot检测结果显示,各组大鼠视网膜中cleved-PARP及GFAP蛋白相对表达量与空白对照组相比,差异均无统计学意义（均为P>0.05）。照度为2000 lux时,除空白对照组和红光照射组外,绿光照射组、蓝光照射组、白光照射组大鼠视网膜TUNEL染色后视网膜感光细胞层均可见细胞核点状阳性着染,提示存在DNA的降解断端;Western blot检测结果显示,蓝光照射组大鼠视网膜中cleved-PARP蛋白表达量（1.414±0.192）较空白对照组（0.624±0.148）增加,差异有统计学意义（P<0.05）,红光照射组（0.660±0.067）、绿光照射组（0.764±0.127）、白光照射组（0.748±0.160）大鼠视网膜cleved-PARP蛋白表达与空白对照组相比,差异均无统计学意义(均为P>0.05);各组大鼠视网膜中GFAP蛋白相对表达量比较,差异均无统计学意义(均为P>0.05)。结论　照度2000 lux、每天10 min光照1个月,蓝光照射的大鼠会出现视网膜光损伤表现。     

视网膜色素变性的视觉电生理和心理物理学检测

目的：观察视网膜色素变性(retinitis pigmentosa，RP)患者视觉电生理与心理物理学的改变，探讨其视网膜的病理生理变化。 方法：对58例(113眼)作暗适应红光和蓝光视网膜电图(electroretinogram,ERG)，明适应白光ERG，黄斑中心色光阈值(color light threshold,CLT)和D-15色相配列检测井进行分析。 结果：113只眼暗适应红光ERG均出现异常。111只眼(98.23%)暗适应蓝光及暗适应白光ERG异常，88只眼(77.87%)黄斑中心CLT异常；作D-15色相配列检查的55只眼中30只眼(54.54%)有不同程度色觉异常。暗适应红光ERGb波波幅与病程、视力及视野间均无明显的相关性。 结论：RP不仅存在视网膜杆体功能异常，锥体功能亦有紊乱．暗适应红光ERG是较全面反映RP患者视网膜功能的简便、敏感的客观检测方法。 （中华眼底病杂志，1995，11：143-146）     

正常SD大鼠视网膜电图随生长发育变化的特点

目的研究正常SD大鼠视网膜电图(ERG)随生长发育的变化特点。方法分别测量40只(40眼)SD大鼠在出生后第14、21、28、35和56d(P14、P21、P28、P35、P56)的ERC。结果正常SD大鼠Max-ERGa波、OPsO1波潜伏期在各个时间点无明显差异;Rod-ERGb波、Max-ERGb波、Cone-ERGb波、OPsO2波潜伏期和波幅值以及OPsO1波和Max-ERGa波幅值、Flick-ERG幅值在P14分别和其他时间点有差异。结论实验在一定程度上证实了正常SD大鼠ERG中各波形的起源。明确了各波形的成熟时间,P21时正常SD大鼠ERG基本发育成熟。     

红蓝光谱视网膜电图在白内障术前的应用

视网膜电图（ERG）是视网膜受光刺激后在视网膜节细胞冲动之前记录的一簇电反应，代表了视感受器到无长突细胞的视网膜各层的电活动”‘。600un。以上波长的红光主要兴奋视锥细胞，而500nnl以下波长的蓝光主要兴奋视杆细胞，故利用光谱中不同波长光作为刺激可分离明、暗视成分。白内障术前进行光谱ERG的检测，可初步了解视网膜功能情况，对术后视力恢复情况作出客观的评估。我科自1995年3月始应用红蓝光谱ER（对白内障术前进行常规检查。现将240例（302眼）白内障术前检查结果分析如下。1材料与方法1．l一般资料正常对照组154例（249眼…     

455nm和610nm单色光照对恒河猴明适应光谱敏感性的影响

目的观察单色光照对恒河猴眼光谱敏感性的影响。方法2月龄恒河猴6只,明适应下记录闪烁光视网膜电图。刺激光范围为415-650nm单色光,各单色光峰值间隔约20nm。光强从最大能量值以0．25log单位依次递减。记录时,光强由低到高,每一次测试间隔5～10S,建立各单色光的光强-振幅函数,以振幅为80uV时的光强值记为I,以单色光波长值为横坐标,Log （I/I）为纵坐标绘制猴眼的光谱敏感曲线。然后将6只恒河猴分别置于红光（610nml、蓝光（455nm）和白光（色温5000k）照射条件下饲养（光照周期8am～8pm）,每组2只。分析光照前以及光照6周后的光谱敏感曲线。结果光照前,恒河猴眼光谱的3个敏感峰值分别在455～475nm（短波长）、515～535nm（中波长）和595—610nm（长波长）3个波段。光照6周后,白光组猴眼光谱曲线与光照前相比,形态和光谱峰值无明显改变;红光组长波长段的敏感峰值降低或消失．而中波长段敏感峰值向长波长段位移,并有增高的趋势;蓝光组的敏感曲线峰值位置基本不变,但整个光谱曲线位置下移,敏感性降低。结论单色光照能引起幼年恒河猴眼光谱曲线振幅和峰值的改变,其机制可能与色觉通路间信号对比改变有关。     

雌激素对光诱导的视网膜电图损害的保护作用

目的:探讨雌激素对光诱导的视网膜电图损害的保护作用。方法:雌性SD大鼠30只,随机分为去势组、去势+雌激素组和正常对照组,每组10只。去势组、去势+雌激素组大鼠接受12h亮12h暗(12∶12)的循环光照射,共14次。行右眼的暗视蓝光ERG、暗视白光ERG检测。结果:正常对照组大鼠暗视蓝光、暗视白光ERGb波振幅分别为87.6±20.2μV、231.2±27.7μV,去势组为24.3±8.4μV、38.5±11.9μV,去势+雌激素组40.0±10.6μV、66.6±17.0μV。去势组与去势+雌激素组之间的差异有显著的统计学差异(q=-3.0129,P=0.005;q=-3.4822,P=0.002)。结论:雌激素对光诱导的视网膜电图损害具有保护作用。     

Muller细胞在增殖性糖尿病性视网膜病变中的作用

目的 评价Muller细胞在糖尿病性视网膜病变(DR)视网膜新生血管形成中的作用.方法 对239例(478只眼)非增殖期、增殖前期及早期增殖期DR病人进行了闪光视网膜电图(ERG)、局部ERG以及12、32、40赫兹闪烁光ERG检查,并计算纤维指数:闪光ERG的b波幅值/12赫兹闪烁光ERG幅值.此外,对37例增殖前期DR病人每间隔2～4个月进行动态电生理观察1～1.5年.结果 非增殖期DR的32、40赫兹闪烁光ERG b波幅值位于正常低限,闪光ERG的a波幅值中度降低,为(54±9.6)μv,b波幅值正常;12赫兹闪烁光ERG幅值明显降低,为(25.8±9.4)μv,纤维指数平均为(9.3±1.4)单位.增殖前期DR的所有视网膜电反应均中度下降,闪光ERG的b波幅值为(179±19)μv,12赫兹闪烁光ERG幅值为(13.0±6.4)μv,纤维指数为10～16单位,平均(13.8±1.3)单位,有极显著增高(P<0.001).早期增殖期DR的闪光视网膜电图的a波和32、40赫兹闪烁光视网膜电图幅值继续下降,分别为(30.0±12.2)μv、(8.8±2.7)μv和(4.o±2.1)μv,纤维指数平均为:(13.5±2.2),有极显著增高(P<0.001).动态观察表明,原来增高的纤维指数突然下降,说明近期出现视网膜新生血管的可能性极大.结论 纤维指数增高是视网膜缺血缺氧的共同特点,表明Muller细胞的代谢活性代偿性增高,证实其在视网膜新生血管形成中起重要作用.     

17β-雌二醇抗BALB/c与C57BL/6小鼠视网膜光照损伤的比较

目的：通过建立BALB/c与C57BL/6小鼠视网膜光损伤模型，研究17β-雌二醇(17β-estradiol， E2)的视网膜神经保护作用，为成功构建E2抗视网膜光损伤模型提供实验数据。

方法：成年雌性BALB/c、C57BL/6小鼠各40～45只，实验分组如下：正常对照组，去势手术对照组，去势光照组(小鼠去势手术14d后进行持续10 000lx白光光照刺激4、8、12、16、24h组)，玻璃体腔注射假手术组，生理盐水组和E2预处理组(去势手术14d后暗适应24h后分别行玻璃体腔注射2μL生理盐水或10^-5mol/L E2)，每组各6只。通过石蜡切片HE染色、TUNEL染色、视网膜电图检测视网膜形态及功能变化。

结果：去势光损组视网膜内核层/外核层厚度从白光10 000lx光照4h组开始显著减小； 玻璃体腔注射E2预处理可显著抑制两种品系小鼠视网膜各层细胞的凋亡(P<0.01)以及C57BL/6小鼠视网膜电图检测中最大混合反应a波和b波波幅的下降(P<0.05)。

结论：相同光照条件对两种品系小鼠光损敏感性存在差异； E2对BALB/c小鼠无论是视网膜形态学及功能学上都产生了保护作用，而对C57BL/6小鼠功能学保护作用显著。     

利用锥体细胞失功能大鼠和先天性静止性夜盲大鼠对视锥与视杆通路振荡电位的分离研究

背景 振荡电位(OPs)是评估视网膜缺血缺氧性疾病视网膜功能变化的重要工具,利用视网膜退行性病变动物模型对视锥、视杆通路起源的OPs特点进行研究非常重要. 目的 在两种自发性视网膜退行性病变模型大鼠中分离视锥、视杆通路,对比分析视杆、视锥通路起源的OPs波的特点. 方法 采用雄性SD大鼠、锥体细胞失功能(RCD)大鼠、先天性静止性夜盲(CSNB)大鼠各6只,以RETI-scan视觉生理记录系统分别在暗适应(12h)和明适应(10 min)条件下,用不同强度的刺激光(-35、-25、-15、-5、0、5 db)进行刺激,记录各组大鼠的闪光视网膜电图(FERG),通过Matlab 7.0的Butterworth滤波提取OPs,采用快速傅里叶变换(FFT)对所得OPs进行频谱分析.结果 暗适应条件下SD大鼠和RCD大鼠的ERG均可见a波和b波,但CSNB大鼠b波阙如;明适应条件下,SD大鼠和CSNB大鼠可见b波,但RCD大鼠各波阙如.暗适应较高刺激光强度下,SD大鼠和RCD大鼠均有低频(主频)和高频(次频)两个明显的频峰,分别为75 ～ 110 Hz、90～120 Hz和90～ 120 Hz、110 ～ 135 Hz;不同刺激光强度下,CSNB大鼠只有一个频峰,为70～100 Hz.而明适应不同刺激光强度下,SD大鼠和CSNB大鼠均只有一个频峰,分别为75～95 Hz和70～85 Hz.明适应条件下与SD大鼠比较,CSNB大鼠b波隐含时延长,b波振幅明显下降,差异均有统计学意义(P＜0.05);暗适应条件下,RCD大鼠b波隐含时和振幅与SD大鼠比较,差异无统计学意义(P＞0.05);与SD大鼠比较,RCD和CSNB大鼠OPs波振幅下降,隐含时延长,差异均有统计学意义(P＜0.05);明适应条件下不同刺激光强度下CSNB大鼠OPs波的隐含时明显长于SD大鼠,振幅明显低于SD大鼠,差异均有统计学意义(P＜0.05). 结论 视锥、视杆通路起源的OPs有不同特性,自发性视网膜退行性改变大鼠的视杆OPs有两个频峰,正常情况下,视杆通路对OPs的贡献比视锥通路大.     

670 nm近红外光对大鼠视网膜光损伤的保护作用

目的 观察670 nm近红外光对SD大鼠的视网膜光损伤模型是否具有保护作用。方法 将32只SD大鼠分成8组,1组为正常对照组; 2组为红外光对照组; 3、5、7组为光损伤组;第4、6、8组为光损伤加近红外光保护组。光损伤剂量为900,1800,2700 lx白光,持续照射3 h;在光损伤前3 h和光损伤后0、24、48 h,保护组先后4次给予50 mW近红外光照射30 min。光损伤后第5天将大鼠置于暗室过夜,第6天作视网膜电图（ERG）检测,并取眼球作病理检查。结果 1组和2组视网膜细胞结构正常,外核层细胞约11层,ERG b波振幅（1088±55）μV。3组和4组900 lx白光持续照射3 h,未造成大鼠视网膜的损伤。5组1800 lx白光持续照射3 h,外核层细胞的减少至1～2层,内节（IS）与外节（OS）结构完全消失;损伤范围占全视网膜的0.48±0.12,损伤厚度占外核层全厚的L5=0.39±0.07,ERG的b波低伏（431±120 ）μV。6组在1800 Lux白光照射前后实施近红外光保护,视网膜损伤范围缩小为M6=0.17±0.12, （P5/6=0.002);损失厚度减少到L6=0.22±0.09 (P5/6<0.01）;ERG b波振幅升高到（1011±83）μV（P5/6<0.001）。2700 lx白光持续照射3 h,7组和8组病理和ERG检查的差异均无统计学意义［损伤面积:M7=0.83±0.09, M8=0.70±0.10, P7/8=0.074;损伤厚度L7=0.81±0.08, L8=0.73±0.08, P=0.17;ERG：H7=（234±26）μV,H8=（253±29）μV,P7/8>0.05］。结论 在一定的照射强度和时间范围内,670 nm近红外光对大鼠视网膜光损伤有明确的保护作用。     

Spectral characteristics of electroretinography in congenital red-green color blindness

There are few conclusive electroretinography (ERG) studies comparing the spectral characteristics in deutans and normals in contrast to protans and normals. The difficulties of research on deutans were thought to be due to problems in detecting the very slight differences in the spectral characteristics between deutans and normal subjects. To record monochromatic ERG responses accurately in deutans, our time-locked scanning method was improved as follows: We used 12 interference filters for stimulus lights with narrow half widths (4-6 nm) and wavelengths of peak transmission arranged at intervals of 10 nm between 520 nm and 600 nm. Each stimulus light was strictly adjusted to an equal energy and checked simultaneously with ERG recordings. Contact lens electrodes were reformed for comfortable fitting to subjects' corneas. The time interval between each stimulation was set at 300 msec and one scanning of all stimulations took only 3.9 sec. ERG bp-waves were recorded in congenital color blindness by scanning monochromatic light stimuli, and spectral responses obtained could be evaluated as a spectral pattern. Different spectral patterns of responses from those of normal subjects and shift of the peak in the spectral response curves were obtained for congenital color blind subjects. The maximal responses were recorded at around 540 nm in protans and at 570-580 nm in deutans under white adaptation. Differences in the response curves were not found between dichromats and anomalous trichromats. Moreover, selective chromatic adaptation disclosed the separate responses of green cone and red cone systems. In normal subjects the peak of the spectral response curves was shifted to around 540 nm by red adaptation and to around 580 nm by blue adaptation. The spectral patterns changed so that they looked like the patterns under white adaptation of protans and deutans, respectively. But in protans and deutans the same spectral response patterns and almost the same wavelengths of the peak in the spectral response curves as those obtained under white adaptation were recorded under chromatic adaptation. This method provides the possibility of differentiating between red and green color blind subjects and normal subjects by the ERG. Defects or marked abnormality in the red cone system in protans and the green cone system in deutans can also be detected. Monochromatic ERGs of deutans were recorded under more intense red adaptation.(ABSTRACT TRUNCATED AT 400 WORDS)     

Colored light stimuli in ERG for differential diagnosis of cone dystrophies]

We recorded electroretinograms (ERG) with white and color stimuli in normal persons and four patients with cone dystrophies. Kodak Wratten-filters in blue, blue-green, green, yellow and red were used for the color flashes. ERGs to all color stimuli were recorded at dark and light adapted conditions with different stimulus intensities, to 30 Hz flicker stimulation and with special filtering for oscillatory potentials. Selective blue cone-responses were obtained using strong blue flashes at a yellow background. Patients with cone dystrophies showed slightly to moderately reduced responses at dark adaptation to blue, blue-green, green and yellow stimuli. Red stimuli elicited only small responses with a markedly delayed b-wave implicit time. The light adapted recordings, flicker responses and oscillatory potentials were reduced to all color stimuli. However, differences between patients with cone dystrophies could be detected concerning the responses to red and green. In two patients the responses were reduced to the same degree to all color stimuli. Another patient had very small responses and no oscillatory potentials to red, but his responses were only moderately reduced to green. A patient with combined red-green cone and rod dystrophy had a blue cone hypersensitivity. Responses to blue and blue-green were large at all stimulus conditions, but responses to all other stimuli were much smaller. The blue cone ERG showed a prominent blue cone response. ERG recording to colored stimuli allows a separation of retinal dysfunction in patients with cone dystrophies.     

硫辛酸烟酸二联体对蓝光致大鼠视网膜损伤的防治作用

目的:探讨硫辛酸烟酸二联体(N2L)对蓝光致SD大鼠视网膜损伤的防治作用及最佳药物剂量,探寻其可能存在的保护机制。方法:选取150-200 g的SPF级雄性SD大鼠36只,随机分为正常对照组、蓝光损伤组、N2L低剂量组(1.0 mg/kg)、N2L中剂量组(2.5 mg/kg)、N2L高剂量组(5.0 mg/kg)及生理盐水组,每组各6只。正常对照组12 h明暗循环饲养,其余组每日接受9 h日常光照,3 h波长455 nm、强度3000±50 lx蓝光照射及12 h黑夜来建立损伤模型,持续14 d。同时每日腹腔注射1 mL对应剂量的药物。14 d后,所有组常规12 h明暗循环再饲养5 d,采用视网膜电图检查。过量麻醉法处死大鼠制备标本,HE染色,在光学显微镜下观察外核层厚度;CheKine^TM超氧化物歧化酶(SOD)活性检测试剂盒检测SOD活性;Western Blot检测大鼠视网膜Caspase-3、醌氧化还原酶1(NQO1)、谷胱甘肽巯基转移酶(GST)、Bcl-2和Bax蛋白表达量。结果:蓝光损伤组暗视ERG 3.0、10.0 (cd·s)/m^2<...     

Electroretinography of short-wavelength-sensitive cones with a LED built-in electrode and its normal values

To record electroretinograms (ERG) produced by short-wavelength-sensitive cone mechanisms (SWS-cone ERG), the authors used three kinds (blue, green, and red) of light-emitting diode (LED) which were built into a contact lens electrode assembly. The LEDs were used as both stimulus and background light sources. ERG was recorded using blue LED after 10 min of yellow light adaptation produced by green and red LEDs. Duration of photo-stimulation was either 2 or 100 ms. ERG recorded in normal human subjects showed two positive waves with 2 ms photo-stimulation. Amplitude of the former positive wave (b1-wave) was attenuated when the luminance of yellow background increased, and the latter positive wave (b2-wave) was attenuated when the color of photo-stimulation was green or red. These findings suggest that middle-wavelength-sensitive and long-wavelength-sensitive cone mechanisms generated the former positive wave (b1-wave) and SWS-cone mechanisms generated the latter positive wave (b2-wave). Ratio of b2-wave-amplitude to b1-wave-amplitude with 2 ms photo-stimulation measured on 39 normal subjects ranged from 0.5 to 2.0. It was concluded that this three-colored LED built-in electrode was useful for recording SWS-cone ERG.     

Color electroretinography

Electroretinograms to white and color stimuli were recorded in four normal subjects and nine subjects with different cone dysfunctions, including protanopia, cone dystrophy, cone dystrophy with supernormal b-waves at dark adaptation, cone dystrophy with missing b-waves during light adaptation and rod-cone dystrophy with blue cone hypersensitivity. Color stimuli were obtained with Kodak Wratten filters in blue, blue-green, green, yellow and red. Electroretinograms to all stimuli were recorded during dark and light adaptation with different stimulus intensities and to 30-Hz flicker stimulation. In protanopia, responses to red during light adaptation and flicker stimulation were reduced. All cone dystrophies showed reduced amplitudes and prolonged implicit times to red when dark adapted. The light-adapted responses were equally reduced to all color stimuli in cone dystrophy and cone dystrophy with supernormal b-waves. Contrary to other cone dystrophies, in cone dystrophy with missing b-waves, responses to red were severely reduced and responses to green were preserved, indicating a predominantly red cone dysfunction. Blue cone hypersensitivity was clearly distinct from other dystrophies in having large responses to blue and blue-green and much smaller responses to all other colors in all stimulus conditions. The electroretinogram with color stimuli allowed separation of different cone dysfunctions and identification of new retinal dysfunction syndromes.     

Color sensation of pseudophakic eye from a viewpoint of electrophysiological study]

Monochromatic ERG b-waves were recorded in normal eyes, cataractous eyes and pseudophakic eyes implanted with non-UV or UV IOLs. ERG b-waves were elicited by fourteen monochromatic stimulus lights ranging from 400 to 660 nm under white light adaptation, and spectral response curves were obtained from b-wave amplitudes. Compared with normal eyes or cataractous eyes, the relative b-wave amplitude of pseudophakic eyes was significantly larger in the short wavelength range from blue to green. Except for 400 nm, the spectral response curve of the eyes implanted with UV IOLs was similar to that of eyes implanted with non-UV IOLs. These results suggested that dyschromatopsia might not only occur in eyes implanted with non-UV IOLs but in eyes with UV IOLs.     

Light-emitting-diode induced retinal damage and its wavelength dependency in vivo

AIM: To examine light-emitting-diode (LED)-induced retinal neuronal cell damage and its wavelength-driven pathogenic mechanisms. METHODS: Sprague-Dawley rats were exposed to blue LEDs (460 nm), green LEDs (530 nm), and red LEDs (620 nm). Electroretinography (ERG), Hematoxylin and eosin (H&E) staining, transmission electron microscopy (TEM), terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and immunohistochemical (IHC) staining, Western blotting (WB) and the detection of superoxide anion (O2-·), hydrogen peroxide (H2O2), total iron, and ferric (Fe3+) levels were applied. RESULTS: ERG results showed the blue LED group induced more functional damage than that of green or red LED groups. H&E staining, TUNEL, IHC, and TEM revealed apoptosis and necrosis of photoreceptors and RPE, which indicated blue LED also induced more photochemical injury. Free radical production and iron-related molecular marker expressions demonstrated that oxidative stress and iron-overload were associated with retinal injury. WB assays correspondingly showed that defense gene expression was up-regulated after the LED light exposure with a wavelength dependency. CONCLUSION: The study results indicate that LED blue-light exposure poses a great risk of retinal injury in awake, task-oriented rod-dominant animals. The wavelength-dependent effect should be considered carefully when switching to LED lighting applications.