中华实验眼科杂志
中華實驗眼科雜誌
중화실험안과잡지
CHINESE JOURNAL OF EXPERIMENTAL OPHTHALMOLOGY
2012年
8期
704-708
,共5页
张绍丹%李维义%王雯倩%黄萍%王宁利%张纯
張紹丹%李維義%王雯倩%黃萍%王寧利%張純
장소단%리유의%왕문천%황평%왕저리%장순
青光眼%急性高眼压%胶质细胞%巢蛋白
青光眼%急性高眼壓%膠質細胞%巢蛋白
청광안%급성고안압%효질세포%소단백
Glaucoma%Acute intraocular hypertension%Glial cell%Nestin
背景 中枢神经系统以及视网膜中的胶质细胞与神经元关系十分紧密,胶质细胞在神经元损伤和修复过程中发挥着重要作用.急性眼压升高引起的视网膜、视神经及视交叉各部位胶质细胞的早期反应特点以及其与视神经损伤的关系目前尚不清楚. 目的 探讨大鼠视网膜、视神经及视交叉的胶质细胞对急性高眼压的早期反应,同时观察神经前体细胞标志物巢蛋白( nestin)在反应性胶质细胞中的表达. 方法 成年雌性Wistar大鼠9只,分为正常对照组3只和急性高眼压组6只,急性高眼压组大鼠采用右眼前房灌注生理盐水的方法升高大鼠眼压至110 mmHg,持续60 min.于术后第3天和第7天用过量麻醉法处死各组动物各3只,摘出眼球分离视神经和大脑标本,并制作冰冻切片.利用Nissl染色的方法测量高眼压眼视网膜内层厚度,观察视网膜和视交叉的大体形态.用βⅢ-tubulin免疫荧光染色法标记视神经内的视网膜神经节细胞(RGCs)轴突,用胶质纤维酸性蛋白(GFAP)和nestin双重标记显示视网膜、视神经及视交叉的胶质细胞反应,并对两组结果进行比较.结果 正常大鼠的视网膜、视神经以及视交叉内均可见到一定量的GFAP阳性胶质细胞,但nestin的表达量很低.急性眼压升高后的第3天,视网膜内丛状层厚度明显变薄,RGCs数目较损伤前减少约46％.视网膜内胶质细胞GFAP的表达显著增加,细胞突起由神经纤维层伸展至整个视网膜,增生的胶质细胞内可见nestin的明显表达.视神经内RGCs轴突发生变性样改变,GFAP阳性胶质细胞内nestin的表达较眼压升高前明显增加.同损伤眼相对应的一侧视交叉的横断面积减小,出现大量星状GFAP和nestin共表达的胶质细胞.以上改变在眼压升高后第7天更趋明显.结论 急性眼压升高早期即可引起RGCs的丢失及轴突的变性,视觉神经元改变的同时伴随胶质细胞的反应,增生的胶质细胞表达神经前体细胞的标志物.视网膜与视神经和视交叉的改变在时间上具有一定的同步性.
揹景 中樞神經繫統以及視網膜中的膠質細胞與神經元關繫十分緊密,膠質細胞在神經元損傷和脩複過程中髮揮著重要作用.急性眼壓升高引起的視網膜、視神經及視交扠各部位膠質細胞的早期反應特點以及其與視神經損傷的關繫目前尚不清楚. 目的 探討大鼠視網膜、視神經及視交扠的膠質細胞對急性高眼壓的早期反應,同時觀察神經前體細胞標誌物巢蛋白( nestin)在反應性膠質細胞中的錶達. 方法 成年雌性Wistar大鼠9隻,分為正常對照組3隻和急性高眼壓組6隻,急性高眼壓組大鼠採用右眼前房灌註生理鹽水的方法升高大鼠眼壓至110 mmHg,持續60 min.于術後第3天和第7天用過量痳醉法處死各組動物各3隻,摘齣眼毬分離視神經和大腦標本,併製作冰凍切片.利用Nissl染色的方法測量高眼壓眼視網膜內層厚度,觀察視網膜和視交扠的大體形態.用βⅢ-tubulin免疫熒光染色法標記視神經內的視網膜神經節細胞(RGCs)軸突,用膠質纖維痠性蛋白(GFAP)和nestin雙重標記顯示視網膜、視神經及視交扠的膠質細胞反應,併對兩組結果進行比較.結果 正常大鼠的視網膜、視神經以及視交扠內均可見到一定量的GFAP暘性膠質細胞,但nestin的錶達量很低.急性眼壓升高後的第3天,視網膜內叢狀層厚度明顯變薄,RGCs數目較損傷前減少約46％.視網膜內膠質細胞GFAP的錶達顯著增加,細胞突起由神經纖維層伸展至整箇視網膜,增生的膠質細胞內可見nestin的明顯錶達.視神經內RGCs軸突髮生變性樣改變,GFAP暘性膠質細胞內nestin的錶達較眼壓升高前明顯增加.同損傷眼相對應的一側視交扠的橫斷麵積減小,齣現大量星狀GFAP和nestin共錶達的膠質細胞.以上改變在眼壓升高後第7天更趨明顯.結論 急性眼壓升高早期即可引起RGCs的丟失及軸突的變性,視覺神經元改變的同時伴隨膠質細胞的反應,增生的膠質細胞錶達神經前體細胞的標誌物.視網膜與視神經和視交扠的改變在時間上具有一定的同步性.
배경 중추신경계통이급시망막중적효질세포여신경원관계십분긴밀,효질세포재신경원손상화수복과정중발휘착중요작용.급성안압승고인기적시망막、시신경급시교차각부위효질세포적조기반응특점이급기여시신경손상적관계목전상불청초. 목적 탐토대서시망막、시신경급시교차적효질세포대급성고안압적조기반응,동시관찰신경전체세포표지물소단백( nestin)재반응성효질세포중적표체. 방법 성년자성Wistar대서9지,분위정상대조조3지화급성고안압조6지,급성고안압조대서채용우안전방관주생리염수적방법승고대서안압지110 mmHg,지속60 min.우술후제3천화제7천용과량마취법처사각조동물각3지,적출안구분리시신경화대뇌표본,병제작빙동절편.이용Nissl염색적방법측량고안압안시망막내층후도,관찰시망막화시교차적대체형태.용βⅢ-tubulin면역형광염색법표기시신경내적시망막신경절세포(RGCs)축돌,용효질섬유산성단백(GFAP)화nestin쌍중표기현시시망막、시신경급시교차적효질세포반응,병대량조결과진행비교.결과 정상대서적시망막、시신경이급시교차내균가견도일정량적GFAP양성효질세포,단nestin적표체량흔저.급성안압승고후적제3천,시망막내총상층후도명현변박,RGCs수목교손상전감소약46％.시망막내효질세포GFAP적표체현저증가,세포돌기유신경섬유층신전지정개시망막,증생적효질세포내가견nestin적명현표체.시신경내RGCs축돌발생변성양개변,GFAP양성효질세포내nestin적표체교안압승고전명현증가.동손상안상대응적일측시교차적횡단면적감소,출현대량성상GFAP화nestin공표체적효질세포.이상개변재안압승고후제7천경추명현.결론 급성안압승고조기즉가인기RGCs적주실급축돌적변성,시각신경원개변적동시반수효질세포적반응,증생적효질세포표체신경전체세포적표지물.시망막여시신경화시교차적개변재시간상구유일정적동보성.
Background Glial cells perform specialized function in many aspects of the development,homeostasis,and function of neurons.Retinal ganglion cells (RGCs)and glia interactions are critically important in glaucomatous neurodegeneration.However,the precise mechanisms of glial activation and ganglion cells damage are still remained unclear. Objective This study was to assess the early responses of glial cells in the retina,optic nerve and optic chiasm in rat models of acute high intraocular pressure (IOP),and to examine the expression of nestin,a neuronal progenitor marker,in the reactive glias. Methods Acute high IOP of 110 mmHg was induced in the right eyes of 6 clean adult female Wistar rats by infusing normal saline solution into the anterior chamber for 60 minutes.Three normal matched Wistar rats were used as controls.The rats were sacrificed by overanaesthesia and sections of retina,optic nerve and optic chiasm were collected on 3 days and 7 days after the injection.Rat retina was examined by Nissl staining to illustrate the gross structure changes.Loss of axons of RGCs in the optic nerve was assessed by immunostaining of β Ⅲ-tubulin.Double labeling of glia] fibrillary acidic protein (GFAP) and nestin was performed in sections of retina,optic nerve and optic chiasm to evaluate the glial responses.The use of the animals complied with Statement of Animal Ethic Committee of Peking University Third Hospital. Results In control rats,GFAP-positive glial cells were observed in the retina,optic nerve and optic chiasm,where only weak positive response for nestin was noticed.Three days after acute IOP elevation,thickness of inner plexus form layer was significantlydecreased in comparison with the control rats.A loss of 46％ RGCs was found in the rats with ocular hypertension.Obvious increase of GFAP expression was displayed in the retina,and processes of GFAP-positive glia cells extended into outer retina accompanied with significant up regulation of nestin.Axons in the optic nerve demonstrated a tendency of degeneration.Nestin expression increased significantly in the GFAP-positive glias in the optic nerve.Cross-sectional area of optic chiasm corresponding to the injured retina decreased relative to its countcrpart.Astrocyte like GFAP and nestin-colabeled glials were observed in this part of optic chiasm.The pathological changes of the retina,optic nerve and optic chiasm in hypertensive eyes aggravated on 7 days. Conclusions Acute ocular hypertension induce early onset of RGCs loss and axon degeneration.Neuronal injury is accompanied with glial reaction.Reactive glial cells express neuronal progenitor markers.The structural changes of the optic nerve and optic chiasm occur simultaneously with the high IOP.
