藏红花素对大鼠视网膜缺血-再灌注损伤的保护作用

目的　观察大鼠视网膜缺血-再灌注损伤（retinal ischemia-reperfusion injury，RIRI）时藏红花素对视网膜细胞凋亡数目、凋亡相关蛋白Caspase-3表达的影响，探讨缺血再灌注时藏红花素对视网膜的保护作用机制。方法　选取体质量200~250 g的健康雄性SD大鼠24只，随机分为4组:对照组、模型组、藏红花素低剂量组和藏红花素高剂量组，每组6只。藏红花素低剂量组、高剂量组分别于造模前3 d、30 min定时腹腔注射5 g·L^-1藏红花素5 mg·kg^-1、50 mg·kg^-1。造模成功后24 h处死大鼠并摘取眼球。使用电镜观察各组大鼠视网膜细胞结构，TUNEL染色检测视网膜凋亡细胞数量，免疫组织化学染色法观察凋亡相关蛋白Caspase-3在视网膜中的表达。结果　视网膜TUNEL染色发现，对照组视网膜组织中几乎未发现凋亡细胞的阳性表达，模型组视网膜神经节细胞层和内核层中发现大量棕黄色着色的细胞，其凋亡细胞数为（27.40±0.96）个，藏红花素低剂量组可见神经节细胞层、内核层凋亡细胞数较模型组减少，凋亡细胞数为（8.40±0.41）个，与模型组相比差异有统计学意义（P<0.01）；藏红花素高剂量组凋亡细胞数较模型组和低剂量组明显减少，凋亡细胞数为（4.30±0.47）个，和藏红花素低剂量组相比差异有统计学意义（P<0.01）。对照组大鼠视网膜组织Caspase-3染色阴性，模型组视网膜神经节细胞层可见棕黄色颗粒位于细胞浆内，藏红花素低剂量组Caspase-3蛋白表达量与模型组类似，藏红花素高剂量组Caspase-3蛋白表达量与对照组类似。结论　藏红花素能通过降低Caspase-3蛋白含量及凋亡细胞数，从而有效保护视网膜免受RIRI。     

替普瑞酮对大鼠慢性高眼压视网膜HSP70表达的影响

目的:研究慢性高眼压大鼠视网膜HSP70表达的变化及替普瑞酮的影响。方法:Wistar大鼠70只随机分为3组:空白对照组10只;慢性高眼压模型组30只;慢性高眼压模型+GGA组30只。采用烧灼巩膜浅层静脉的方法制备大鼠慢性高眼压模型。模型成功后给予替普瑞酮800mg/(kg.d)每日灌胃。应用免疫组织化学方法观察应用及未应用替普瑞酮的慢性高眼压大鼠视网膜不同时点的差异及HSP70表达的变化。结果:平均眼压高于正常眼压40%的手术眼为造模成功。与正常对照组相比,慢性高眼压大鼠应用与未应用替普瑞酮者,视网膜均随着高眼压时间的延长逐渐出现形态学变化,于高眼压的21d和28d视网膜变薄,节细胞数量减少;在此过程中,HSP70表达增多。慢性高眼压大鼠视网膜应用替普瑞酮者与未应用提普瑞酮者相比,其形态学变化较小,而HSP70表达则明显增多,两者差异具有统计学意义(P<0.01)。结论:替普瑞酮通过上调HSP70表达发挥对慢性高眼压视网膜的保护作用。     

替普瑞酮对大鼠慢性高眼压视网膜HSP70表达的影响

目的：研究慢性高眼压大鼠视网膜HSP70表达的变化及替普瑞酮的影响。方法：Wistar大鼠70只随机分为3组：空白对照组10只;慢性高眼压模型组30只;慢性高眼压模型＋GGA组30只。采用烧灼巩膜浅层静脉的方法制备大鼠慢性高眼压模型。模型成功后给予替普瑞酮800mg／（kg·d）每目灌胃。应用免疫组织化学方法观察应用及未应用替普瑞酮的慢性高眼压大鼠视网膜不同时点的差异及HSP70表达的变化。结果：平均眼压高于正常眼压40％的手术眼为造模成功。与正常对照组相比,慢性高眼压大鼠应用与未应用替普瑞酮者,视网膜均随着高眼压时间的延长逐渐出现形态学变化,于高眼压的21d和28d视网膜变薄,节细胞数量减少;在此过程中,HSP70表达增多。慢性高眼压大鼠视网膜应用替普瑞酮者与未应用提普瑞酮者相比,其形态学变化较小,而HSPT0表达则明显增多,两者差异具有统计学意义（P〈0．01）。结论：替普瑞酮通过上调HSP70表达发挥对慢性高眼压视网膜的保护作用。     

热休克反应对大鼠视网膜缺血再灌注损伤的防御作用

目的 观察热休克反应对大鼠视网膜缺血再灌注损伤的防御作用。 方法 将20只Wistar大鼠20只眼随机分为4组，每组5只大鼠。行前房灌注（perfusion）平衡盐溶液制造急性高眼压模型,为高眼压组(P组)；在制造急性高眼压模型前24 h向大鼠腹腔内注射槲皮素(quercetin) (400 mg/kg)，为高眼压＋槲皮素组(P+Q组)；在制造急性高眼压模型前24 h 热休克(heat shock)大鼠，为高眼压＋热休克组(P+H组)；分别在制造急性高眼压模型前48 、24 h，向大鼠腹腔内注射槲皮素、热休克大鼠，为高眼压＋槲皮素+热休克组(P+Q+H组) 。按照国际临床视觉电生理学会的标准化方案，采用国特医疗系统对热休克反应后实验性高眼压大鼠模型和HSP70被槲皮素特异性抑制后实验性高眼压大鼠模型进行暗适应视网膜电图(dark adapted electroretinogram, D-ERG)、振荡电位(oscillatory potentials, OPs)和明适应E RG(light adapted ERG, L-ERG)记录。采用Western blotting方法检测各组大鼠视网膜HSP 70表达情况。 结果 P+H组大鼠视网膜HSP70表达在各组大鼠中最高，P+Q、P+Q+H组大鼠视网膜HSP70表达受到抑制。前房灌注后各组大鼠ERG各波潜伏期延长、幅值减小，P+H组D-ERG的b波、OPs的O₂波的幅值较P组高。灌注0 h后，P+H组各波幅值显著增高(P值均<0.05)；灌注24 h 后，P+H组大鼠视网膜功能恢复较P组好。P+Q、P+Q+H组大鼠灌注后ERG各波及OPs的O₂波潜伏期最长，幅值最低，甚至消失。 结论 热休克反应可以提高大鼠视网膜细胞对缺血再灌注损伤的防御作用。 （中华眼底病杂志，2003，19：117-120）     

替普瑞酮对大鼠慢性高眼压视网膜热休克蛋白70表达的影响

青光眼视神经损害的机制最终为视网膜神经节细胞（retinal ganglion cells,RGCs）的凋亡,热休克蛋白（heatshockprotein,HSP）是生物细胞在受热或其他许多损伤因素应激刺激下产生的具有高度保守性的特异蛋白质家族,其中HSP70是在中枢神经系统中含量最丰富的HSP,能通过分子伴侣作用及抑制神经元凋亡等发挥神经保护作用。研究证实,替普瑞酮可以明显诱导胃肠黏膜、肝脏、心脏等组织的HSP70表达。     

缺血预处理对大鼠视网膜缺血再灌注损伤保护作用

目的：探讨缺血预处理是否对视网膜缺血再灌注损伤有保护作用及其机理,方法：利用前房灌注生理盐水形成高眼压的视网膜缺血再灌注损伤的动物模型,视网膜缺血时间为1h分别于缺血前30min、24h或72h对大鼠一只眼5min短暂缺血即预处理,24h或72h后行视网膜电图（ERG）、电镜、光镜、丙二醛（MDA）及热休克蛋白70（HSP70）检测,或者一侧眼行5min假处理,24h后行1h缺血,24h或72h再行上述检测,所有对侧眼不作处理作对照,结果：与假处理相相比,缺血前24、72h进行预处理后的大鼠视网膜光镜、电镜表现损害明显减轻,ERGb波明显恢复（P＜0．01）,MDA含量降低（P＜0．01）,缺血前30min预处理的视网膜表现严重的损害,ERGb波几安全消失,结论：缺血预处理对视网膜缺血再灌注损伤有保护作用,且有一定时限性。     

替普瑞酮对青光眼视神经保护作用的研究进展

青光眼是当今世界范围内的主要致盲性眼病之一,其病理基础是视网膜神经节细胞（RGCs）的不断丢失及其轴突数目的不断减少。目前的研究发现,热休克蛋白70（HSP70）可有效减少高眼压所致的视神经损害,保护视神经。替普瑞酮（GGA）可诱导HSP70在视网膜的表达,并通过减少细胞凋亡发挥神经保护作用,减轻神经元损害,增加神经元的存活,从而为治疗青光眼提供了新前景。     

葛根素对大鼠视网膜缺血再灌注损伤的保护作用

目的观察葛根素(puerarin)对大鼠视网膜缺血再灌注的保护作用及机制。方法成年Wistar大鼠随机分成对照组、缺血再灌注未治疗组、缺血再灌注葛根素治疗组。采用前房灌注液体形成高眼压而建立RIR模型。治疗组在缺血前30min给予大鼠腹腔内注射葛根素。缺血60min后恢复血流。光镜观察各组视网膜内层厚度以及浸润入视网膜的中性粒细胞数目、神经节细胞数变化;免疫组化法检测Caspase-3蛋白在各组视网膜中的表达。结果葛根素治疗组再灌注6h以后各时间段视网膜内层厚度均较未治疗组视网膜缺血再灌注厚,早期视网膜内层水肿增厚,晚期视网膜神经节细胞数目减少及视神经纤维层萎缩变薄,神经节细胞数目多于未治疗组,而视网膜中的中性粒细胞数目少于未治疗组;Caspase-3蛋白于再灌注后24h达到高峰,但各时间段治疗组表达强度均较未治疗组明显减弱。结论葛根素对视网膜缺血再灌注损伤有治疗作用,抑制缺血再灌注损伤后的炎症反应和Caspase-3蛋白的表达是其可能的保护机制。     

缺血后适应对视网膜缺血-再灌注损伤的保护作用

背景研究证明,缺血后适应（IPC）对多种组织器官的缺血缺氧损伤均有一定的抵抗作用,但其对视网膜缺血缺氧的作用仍受到关注。目的探讨IPC对大鼠视网膜缺血-再灌注损伤（RIRI）后视网膜结构和功能的保护作用。方法将36只健康雄性Wistar大鼠以随机数字表法分为正常对照组、伪手术组、缺血-再灌注组、IPC组。利用前房灌注生理盐水升高眼压至100mmHg（1mmHg=0．133kPa）维持60min的方法制备RIRI大鼠模型,实施IPC处理鼠亚分为再灌注后即刻、1min、10min组（即IPCⅠ组、IPCⅡ组、IPCⅢ组）,分别于实验后1d、7d行大鼠视网膜电图（ERG）检测,然后用过量麻醉法处死大鼠并制备视网膜切片,行苏木精-伊红染色,对各组大鼠视网膜厚度的变化和视网膜形态进行观察。采用SPSS13．0统计学软件的单因素方差分析对各组大鼠ERG各波振幅恢复率和视网膜厚度值的差异进行比较。结果实验后1d,与正常对照组大鼠比较,伪手术组大鼠视网膜结构接近正常,而缺血-再灌注组及IPCⅠ组、IPCⅡ组、IPCⅢ组大鼠视网膜均出现水肿,可见空泡变性,主要在内丛状层（IPL）及内核层（INL）。缺血-再灌注组及IPCⅠ组、IPCⅡ组、IPCⅢ组大鼠视网膜全层、INL、IPL及视网膜外层厚度值均明显高于正常对照组,差异均有统计学意义（均P〈0．05）。再灌注后7d,缺血-再灌注组大鼠视网膜全层厚度值明显低于正常对照组,差异均有统计学意义（均P〈0．05）,尤以INL、IPL显著。IPCⅠ组、IPCⅡ组、IPCⅢ组大鼠视网膜全层、INL、IPL及视网膜外层厚度值均明显高于缺血-再灌注组,差异均有统计学意义（均P〈0．05）。再灌注后7d,缺血-再灌注组、IPC各组大鼠ERG a波、b波和OPs振幅恢复率明显低于伪手术组和正常对照组大鼠,差异均有统计学意义（均P〈0．05）;而IPCⅠ组、IPCⅡ组、IPCⅢ组大鼠ERG a波、b波和OPs振幅恢复率明显高于缺血-再灌注组,差异均有统计学意义（均P〈0,05）。结论IPC对RIRI具有保护作用,在大鼠模型中,这种保护作用在再灌注后即刻至1min时最强。     

重组人促红细胞生成素对大鼠视网膜缺血-再灌注损伤的保护作用

目的 制作Sprague-Dawley (SD)大鼠视网膜缺血-再灌注(RIR)损伤模型,探讨腹腔内注射重组人促红细胞生成素(rHuEPO)对急性RIR损伤所致的大鼠视网膜神经元损伤的保护作用及其对热休克蛋白72(HSP72)表达的影响.方法 采用前房灌注的方式建立RIR损伤模型,灌注压110 mm Hg(1 mm Hg=0.133kPa),缺血时间1h;腹腔注射rHuEPO.78只SD大鼠随机分组:正常组6只,EPO组、EPO+槲皮黄酮组、RIR组各24只,均以右眼为实验眼.采用免疫组织化学法和末端脱氧核苷酸转移酶介导的dUTP缺口末端标记法(TUNEL)分别测定正常对照组和各实验组大鼠再灌注24h、48 h、72 h和1周视网膜中HSP72及凋亡细胞的表达,观察各组大鼠视网膜病理学改变.结果 ①正常组大鼠视网膜中HSP72表达微弱,各实验组大鼠视网膜中HSP72表达自再灌注12 h开始增强,24h达到高峰,随后逐渐减弱,72 h时表达稍高于正常.再灌注后各时间段,EPO组大鼠视网膜中HSP72表达均高于RIR组、EPO+槲皮黄酮组(P＜0.05).②正常大鼠视网膜中几乎没有凋亡细胞.再灌注后12 h,各实验组大鼠视网膜中可见凋亡细胞,24 h达高峰,48 h后凋亡细胞数逐渐减少;再灌注后各组大鼠视网膜中凋亡细胞数比正常组多(P＜0.05).③再灌注后,RIR组,EPO+槲皮黄酮组大鼠内层视网膜明显水肿,炎性细胞侵入,膜结构逐渐破坏;EPO组大鼠视网膜结构保持相对完整,炎性细胞相对较少.结论 ①HSP72在正常大鼠视网膜中表达微弱,RIR损伤后表达增多.腹腔注射EPO可以明显诱导大鼠视网膜中HSP72的表达增多.②EPO可以减少大鼠RIR损伤后视网膜细胞凋亡,减少视网膜内炎性细胞的浸润,保护视网膜结构,对视网膜具有明显的保护作用.其机制可能与使HSP72表达上调有关.(中国眼耳鼻喉科杂志,2012,12:30-35)     

Protective effects of pentoxifylline in retinal ischemia/reperfusion injury

We studied the effect of pentoxifylline on retinal lipid peroxidation and histopathologic changes due to ischemia/reperfusion (I/R). A total of 15 pigmented male guinea pigs were divided into 3 equal groups as control, sham and treatment groups. After application of high intraocular pressure for 90 min for the induction of retinal ischemia, 24-hour reperfusion was established in the sham and treatment groups. In the treatment and sham groups, either 45 mg/kg of pentoxifylline or saline was given 3 times at 8-hour intervals. Biochemical assay and histopathologic evaluation were performed on one randomly selected eye of each animal which was enucleated at the end of the reperfusion period, and retinal malondialdehyde (MDA) levels and thickness of the retinal tissue were determined for each group. The mean MDA level of the sham group was significantly higher versus the control and treatment groups (p < 0.001). When compared with the control group, the mean MDA level of the treatment group was slightly higher, but the difference was not statistically significant (p > 0.05). In comparison with the control group there was a significant increase in the thickness of the retina in the sham group (p < 0.0001), and no significant difference was found in the retinal thickness of the treatment group (p > 0.05). Pentoxifylline might have a preventive effect on the I/R injury of the retina.     

Protective effects of catalase on retinal ischemia/reperfusion injury in rats

Retinal ischemia/reperfusion (I/R) injury causes profound tissue damage, especially retinal ganglion cell (RGC) death. The aims of the study were to investigate whether catalase (CAT) has a neuroprotective effect on RGC after I/R injury in rats, and to determine the possible antioxidant mechanism. Wistar female rats were randonmized into four groups: normal control group (Control group), retinal I/R with vehicle group (I/R with vehicle group), retinal I/R with AAV-CAT group (I/R with AAV-CAT group), and normal retina with AAV-CAT group (normal with AAV-CAT group). One eye of each rat was pretreated with recombinant adeno-associated virus containing catalase gene (I/R with AAV-CAT group or normal with AAV-CAT group) and recombinant adeno-associated virus containing GFP gene (I/R with vehicle group) by intravitreal injection 21 days before initiation of I/R injury. Retinal I/R injury was induced by elevating intraocular pressure to 100 mmHg for 1 h. The number of RGC and inner plexiform layer (IPL) thickness were measured by fluorogold retrograde labeling and hematoxylin and eosin staining at 6 h, 24 h, 72 h and 5d after injury. Hydrogen peroxide (H₂O₂), the number of RGC, IPL thickness, malondialdehyde(MDA), 8-hydroxy-2-deoxyguanosine (8-OHdG), CAT activity and nitrotyrosine were measured by fluorescence staining, immunohistochemistry and enzyme-linked immunosorbent assay analysis at 5 days after injury. Electroretinographic (ERG) evaluation was also used. Pretreatment of AAV-CAT significantly decreased the levels of H₂O₂, MDA, 8-OHdG and nitrotyrosine, increased the catalase activity, and prevented the reduction of a- and b- waves in the I/R with AAV-CAT group compare with the I/R with vehicle group (p < 0.01). Catalase attenuated the I/R-induced damage of RGC and IPL and retinal function. Therefore, catalase can protect the rat retina from I/R-induced injury by enhancing the antioxidative ability and reducing oxidative stress, which suggests that catalase may be relevant for the neuroprotection of inner retina from I/R-related diseases.     

己酮可可碱对大鼠急性高眼压性视网膜缺血再灌注损伤的保护作用

目的:探讨己酮可可碱对大鼠视网膜缺血再灌注损伤的保护作用及机制。方法:视网膜缺血再灌注模型是通过提高前房眼内压来实现的。将35只Wistar大鼠随机分为3组:正常组5只,对照组15只,治疗组15只。治疗组于高眼压前6h和眼压正常后即刻己酮可可碱50mg/kgip,对照组于相同时间点等容量生理盐水ip。监测视网膜电流图(ERG)b波的变化,测定视网膜谷氨酸含量以及视网膜线粒体钙含量。结果:治疗组和对照组谷氨酸含量都在缺血再灌注后逐渐上升,在48h达到峰值,两组都明显高于空白对照组(P<0.01)。在6h点治疗组与对照组间无显著差异,在其他时点对照组的Glu含量明显高于治疗组(P<0.05)。治疗组和对照组视网膜线粒体钙含量在缺血再灌注后逐渐上升,在24h达到峰值,然后逐渐下降。两组都明显高于空白对照组(P<0.01)。在6h点治疗组与对照组间无显著差异,在其他时点对照组的视网膜线粒体钙浓度明显高于治疗组(P<0.05)。再灌注后,对照组ERGb波比较低平;再灌注后1h,对照组、治疗组的ERG相对b波无明显的差异。24h后两组b波都降低到最低,然后逐渐恢复;72h后对照组ERGb波仅恢复到正常眼的69%左右。己酮可可碱处理组ERGb波恢复到正常眼的95%左右,ERGb波明显较对照组高(P<0.01)。结论:己酮可可碱能有效降低视网膜谷氨酸含量及视网膜组织细胞线粒体钙离子含量,促进ERGb波的恢复,缩短了视网膜缺血再灌注的病理过程。对大鼠视网膜缺血再灌注损伤有一定的保护作用。     

复方五花血藤对鼠视网膜缺血再灌注损伤的保护作用

目的　探讨复方五花血藤对大鼠视网膜缺血再灌注损伤的保护作用。方法　采用健康成年ＳＤ大鼠９０只,随机分为正常对照组、模型组和治疗组,其中模型组和治疗组建立视网膜缺血再灌注模型,治疗组于造模前连续３ｄ给予复方五花血藤灌胃,每天２次（总剂量为１０ｇ?ｋｇ－１?ｄ－１）,模型组和正常对照组灌服相同剂量的生理盐水。通过ＨＥ染色、透射电镜观察再灌注６ｈ、１２ｈ、２４ｈ、４８ｈ与７２ｈ各组大鼠视网膜的形态学变化,原位杂交方法检测各组视网膜凋亡相关因子ｓｕｒｖｉｖｉｎ的表达情况。结果　与正常对照组相比,模型组再灌注后６ｈ视网膜神经节细胞层高度水肿,内丛状层明显增厚,部分视网膜神经节细胞发生空泡变性,但随时间延长病变逐渐减轻。治疗组各时间点视网膜损伤均较模型组轻。与正常对照组相比,模型组ｓｕｒｖｉｖｉｎ在再灌注后６ｈ即开始增加,２４ｈ达到高峰,以后逐渐下降,但各时间点均高于正常对照组（均为Ｐ＜０．０５）。与模型组相比,治疗组ｓｕｒｖｉｖｉｎ各时间点表达均较高（均为Ｐ＜００５）。结论　初步证实复方五花血藤对于大鼠视网膜缺血再灌注损伤有较为明显的保护作用,此研究对于临床药物的开发和利用具有积极意义。     

E-64d对大鼠视网膜缺血再灌注损伤中Calpain和Caspase-3表达的调控作用

目的 探讨E-64d（半胱氨酸蛋白酶抑制剂及钙激活中性蛋白酶抑制剂）在大鼠视网膜缺血再灌注损伤（RIRI）中对Calpain／Caspase-3表达的调节作用。方法 将80只SD大鼠随机分为正常组、视网膜缺血再灌注组、对照组和E-64d治疗组，并分为1、3、6、24、72h5个时间段。通过前房穿刺加压法制成RIRI动物模型，采用Western—blot以及RT—PCR方法测定在大鼠RIRI模型中的Calpian、Caspase-3蛋白和mRNA表达情况。结果缺血再灌注24hm—Calpain、Caspase-3蛋白的表达缺血再灌注组较正常组上升，而E-64d组表达与正常组相似，比缺血再灌注组下降。E-64d能下调视网膜缺血再灌注后m—calpain／calpastatin的mRNA比值，在24h与缺血组有显著统计学差异。结论 E-64d能降低视网膜缺血再灌注时m—Calpain、Caspase-3蛋白的表达，调控m—Calpain和Calpastatin的mRNA比值。     

Protective effects of antithrombin III on retinal ischemia/reperfusion injury in rats: a histopathologic study

PURPOSE: To investigate the effect of antithrombin III (AT III) on retinal ischemia/reperfusion (I/R) injury in rats. METHODS: The study was carried out on 10 Wistar albino rats (20 eyes) and four-vessel occlusion method was employed to induce retinal ischemia in this study. Rats were divided into two groups: Group I (control group, 10 eyes) and Group II (AT III, 10 eyes). In both groups, vertebral arteries were occluded bilaterally an electric needle coagulator under an operating microscope. A total of 48 hours after the initial procedure, the rats were re-anesthetized and both common carotid arteries were clamped to interrupt blood flow. In Group II, rats were injected intravenously with 250 U/kg of AT III 5 minutes before the induction of ischemia. Duration of ischemia was 30 minutes. At the end of this period, clamp was removed for the reperfusion of the eye for 4 hours. Following the reperfusion period, the animals were killed by decapitation. Retinal sections were evaluated under light and electron microscope. The signs of I/R injury at the microscopic level, i.e., cellular degeneration, vacuolization between retinal layers, increase in the retinal thickness due to edema, mononuclear cell infiltration, and apoptotic cells, were recorded for each group. RESULTS: Retinal sections obtained from the rats in the AT III group revealed a well preserved retinal structure. When average thickness values of the two groups were compared to each other, the difference was significant with respect to inner nuclear and inner plexiform layers indicating increased retinal thickness values in Group I due to tissue edema resulting from I/R injury. Similarly, mononuclear cell infiltration and apoptotic cell counts were found to be significantly higher in control group compared to AT III group showing the inhibitory effect of AT III on leukocyte infiltration and apoptotic cell death in rat retina. CONCLUSIONS: Antithrombin III attenuated I/R injury in rat retina.     

孕酮对急性高眼压大鼠视网膜神经损伤保护作用的研究

目的：通过建立大鼠急性高眼压模型,应用孕酮干预,观察孕酮是否对视网膜神经细胞具有保护作用。

方法：Wistar大鼠140只,随机分为正常对照组(A组)20只、高眼压对照组(B组)60只、高眼压孕酮干预组(C组)60只。应用生理盐水前房灌注的方法建立大鼠急性高眼压模型,C组在高眼压后即刻予腹腔注射孕酮4.0mg/kg,以后于6,24h以及隔日行皮下注射,B组于相同时间注射等量的生理盐水。于高眼压后1,3,7d分别获取各组大鼠的视网膜组织。HE染色观察视网膜病理学的变化,用免疫组化染色、Western blot检测视网膜细胞凋亡基因Caspase-3蛋白的表达情况,TUNEL法检测细胞的凋亡程度,并对各组数据进行统计学分析。

结果：B组和C组的大鼠视网膜均发生水肿, C组水肿程度明显低于B组。免疫组化染色及Western blot相对定量检测,C组Caspase-3表达程度低于B组。Caspase-3蛋白主要表达于视网膜神经节细胞层和内核层,于高眼压后第1d强度最大,以后随时间的推移逐渐减少。TUNEL检测细胞凋亡,B组和C组均出现阳性细胞,主要位于视网膜的节细胞层和内核层,C组细胞凋亡数量明显低于B组。

结论：孕酮对大鼠视网膜急性高眼压损伤有保护作用。     

尼莫地平对兔视网膜缺血再灌注损伤保护作用的实验研究

目的　探讨尼莫地平对实验性视网膜缺血再灌注损伤的保护作用及其机理。方法　 72只兔随机分为阴性对照组、模型组、尼莫地平组 ,经前房恒压 ( 110mmHg) ( 1kPa =7.5mmHg)灌注生理盐水 6 0min ,建立视网膜缺血损伤的动物模型。并于造模前 6h及 1h尼莫地平组行尼莫地平溶液灌胃 ,模型组及对照组予等量生理盐水灌胃。观察缺血再灌注损伤后 1、3、7、15d各组视网膜组织学及超微结构变化 ,计数视网膜神经节细胞 (retinalganglioncells,RGC) ,视网膜内层厚度 (thicknessofinnerretinallayers ,TIRL) ,测定丙二醛(malondialdehyde,MDA)、超氧化物歧化酶 (superoxidedismutase,SOD)含量。 结果　模型组再灌注后 1d ,视网膜各层结构即有不同程度的损伤 ,3、7、15d出现节细胞数目减少 ,视网膜内层厚度变薄 ,伴随MDA升高和SOD降低 ,上述变化随时间延长而加重。尼莫地平治疗组RGC和TIRL均从第 3天开始较模型组有显著性增加 ,RGC计数 7d时增加最显著 (P <0 .0 1) ;IRL厚度 15d时增加最显著 (P <0 .0 1)。尼莫地平组各时间点MDA含量均低于模型组 ,而SOD活性都高于模型组 ,差异有显著性。各时间点RGC计数减少和IRL厚度降低呈显著正相关 (r =0 .90 5 ,F =2 7.2 7,P <0 .0 1) ;视网膜MDA含量的降低和SOD活性的升高呈显著     

Effect of trimetazidine on retinal ischemia/reperfusion injury in rats

PURPOSE: To investigate the effect of trimetazidine (TMZ), an antioxidant agent, on the ischemia/reperfusion (I/R) injury in rat retina histopathologically. METHODS: The retinal I/R model was carried out by the 4-vessel occlusion method on Wistar albino rats. Twenty-one rats were divided into 7 groups, each comprising 3 rats. The animals in groups 1, 2 and 3 underwent 30 min of ischemia + 4 h of reperfusion and were treated by the administration of saline, TMZ before reperfusion and TMZ before ischemia, respectively. The animals in groups 4, 5 and 6 underwent 90 min of ischemia + 4 h of reperfusion and were treated in the same way as those in groups 1, 2 and 3, respectively. The 7th group was sham operated. RESULTS: Thirty and 90 min of ischemia followed by 4 h of reperfusion induced retinal injury in the rat retina. Histopathologically, the inner plexiform and inner nuclear layers were the most affected parts. TMZ was able to reduce almost all retinal I/R damage when administered before ischemia. A cytoprotective effect of TMZ was partly observed in those animals which were treated before reperfusion. CONCLUSION: TMZ seemed to have a protective effect against retinal I/R injury in rats.