视网膜Mailer细胞调控豚鼠形觉剥夺性近视形成的研究

目的研究视网膜Maller细胞在豚鼠形觉剥夺性近视形成中的作用。方法眼罩遮盖建立豚鼠形觉剥夺性近视眼模型，分为正常对照组、DL—α-氨基己二酸（DL—α—AAA）组、生理盐水组、遮盖组、遮盖＋DL—d—AAA组、遮盖＋生理盐水组。DL-α-AAA组和遮盖＋DL-α—AAA组右眼玻璃体内注射8μgDL—α—AAA。14d后检影验光测屈光度，A型超声测眼轴长度，免疫组织化学、Western blotting检测视网膜中Vimentin的表达，TUNEL染色检测凋亡细胞。结果眼罩遮盖14d后，豚鼠遮盖眼眼轴延长，近视形成。Vimentin蛋白阳性表达于视网膜MUller细胞。DL—α-AAA组右眼远视度数高于正常对照组，但视网膜Vimentin蛋白表达量下调（P〈0，05）。DL-α-AAA引起遮盖眼近视度数减轻、视网膜Vimentin蛋白表达量下调（P〈0．05）。各实验组的视网膜均未发现凋亡细胞。结论玻璃体内注射DL—α-AAA能特异性作用于视网膜Mtiller细胞，有效抑制豚鼠眼球正视化和近视形成。     

豚鼠近视眼视网膜Müller细胞中TGFβ2、VIP、DA的表达

目的 研究转化生长因子β2(TGFβ2)、血管活性肠肽(VIP)和多巴胺(DA)在原代培养的豚鼠近视眼视网膜Müller细胞中的变化.方法 眼罩遮盖诱导豚鼠近视眼,酶消化法原代培养其视网膜Müller细胞,GFAP、Vimentin免疫组织化学染色进行细胞鉴定.Westren blotting检测TGFβ2、VIP、酪氨酸羟化酶(TH)蛋白在正常对照眼、自身对照眼和近视眼视网膜Müller细胞中的表达情况.高效液相色谱-电化学法测定视网膜Müller细胞分泌DA的质量浓度变化.结果 眼罩遮盖14d后,豚鼠遮盖眼眼轴延长,近视形成.酶消化法成功培养出豚鼠视网膜Müller细胞,95%以上的培养细胞阳性表达GFAP和Vimentin.正常对照眼、自身对照眼和遮盖眼视网膜Müller细胞均阳性表达TGFβ2、VIP、TH蛋白,遮盖眼表达TGFβ2和VIP蛋白上调(P＜0.05)、TH蛋白下调(P＜0.05).与正常对照眼、自身对照眼比较,遮盖眼视网膜Müller细分泌DA减少.结论 Müller细胞是视网膜近视信号因子TGFβ2、VIP和DA的一个重要来源.在近视发生过程中Müller细胞可能通过合成、分泌这些近视信号因子,参与近视发生的调控.     

视网膜Müller细胞调控豚鼠形觉剥夺性近视形成的研究

目的 研究视网膜Müller细胞在豚鼠形觉剥夺性近视形成中的作用.方法 眼罩遮盖建立豚鼠形觉剥夺性近视眼模型,分为正常对照组、DL-α-氨基己二酸(DL-α-AAA)组、生理盐水组、遮盖组、遮盖+DL-α-AAA组、遮盖+生理盐水组.DL-α-AAA组和遮盖+DL-α-AAA组右眼玻璃体内注射8 μg DL-α-AAA.14 d后检影验光测屈光度,A型超声测眼轴长度,免疫组织化学、Western blotting检测视网膜中Vimentin的表达,TUNEL染色检测凋亡细胞.结果 眼罩遮盖14 d后,豚鼠遮盖眼眼轴延长,近视形成.Vimentin蛋白阳性表达于视网膜Müller细胞.DL-α-AAA组右眼远视度数高于正常对照组,但视网膜Vimentin蛋白表达量下调(P＜0.05).DL-α-AAA引起遮盖眼近视度数减轻、视网膜Vimentin蛋白表达量下调(P＜0.05).各实验组的视网膜均未发现凋亡细胞.结论 玻璃体内注射DL-α-AAA能特异性作用于视网膜Müller细胞,有效抑制豚鼠眼球正视化和近视形成.     

豚鼠近视眼视网膜Müller细胞近视因子基因的表达

目的研究视网膜近视因子基因在原代培养的豚鼠近视眼视网膜Müller细胞中的表达变化。方法3～4周龄断乳三色豚鼠40只,取20只建立近视眼模型（以右眼作为实验眼,以对侧未遮盖眼作自身对照）,剩余的20只豚鼠作正常对照。用眼罩遮盖法建立豚鼠近视眼模型,用酶消化法原代培养其视网膜Müller细胞。RT-PCR检测酪氨酸羟化酶（tyrosine hydroxylase,TH）、诱导型一氧化氮合成酶（induciblenitric oxide synthase,iNOS）、神经型一氧化氮合成酶（neu-ronal nitric oxide synthase,nNOS）、内皮型一氧化氮合成酶（endothelial nitric oxide synthase,eNOS）、视黄醛脱氢酶（retinaldehyde dehydrogenase,RALDH）、醛脱氢酶（aldehydedehydrogenase,ALDH）、碱性成纤维细胞生长因子（basic fi-broblast growth factor,bFGF）、转化生长因子β（transforminggrowth factor-β,TGF-β）的mRNA在正常对照眼、自身对照眼和近视眼视网膜Müller细胞中的表达情况。数据分析采用One-way ANOVA检验。结果眼罩遮盖10d后,遮盖眼眼轴延长,近视形成。酶消化法成功培养出视网膜Müller细胞。正常对照眼、自身对照眼和遮盖眼视网膜Müller细胞均阳性表达nNOS、bFGF、TH、TGF-βmRNA,且遮盖眼表达nNOS、bFGF和TGF-βmRNA上调（P〈0.05）,TH mRNA下调（P〈0.05）。iNOS mRNA仅在遮盖眼视网膜Müller细胞阳性表达。三组视网膜Müller细胞均不表达eNOS、RALDH和ALDHmRNA。结论豚鼠近视眼视网膜Müller细胞表达nNOS、iNOS、bFGF和TGF-βmRNA上调,TH mRNA下调。Müller细胞是近视眼视网膜信号因子一氧化氮（nitric oxide,NO）、多巴胺（dopamine,DA）、bFGF和TGF-β的一个重要来源。     

豚鼠近视眼视网膜Müller细胞中TGFβ2、VIP、DA的表达

目的研究转化生长因子β2（TGFβ2）、血管活性肠肽（VIP）和多巴胺（DA）在原代培养的豚鼠近视眼视网膜Müller细胞中的变化。方法眼罩遮盖诱导豚鼠近视眼,酶消化法原代培养其视网膜Müller细胞,GFAP、Vimentin免疫组织化学染色进行细胞鉴定。Westren blotting检测TGFβ2、VIP、酪氨酸羟化酶（TH）蛋白在正常对照眼、自身对照眼和近视眼视网膜Müller细胞中的表达情况。高效液相色谱-电化学法测定视网膜Müller细胞分泌DA的质量浓度变化。结果眼罩遮盖14d后,豚鼠遮盖眼眼轴延长,近视形成。酶消化法成功培养出豚鼠视网膜Müller细胞,95%以上的培养细胞阳性表达GFAP和Vimentin。正常对照眼、自身对照眼和遮盖眼视网膜Müller细胞均阳性表达TGFβ2、VIP、TH蛋白,遮盖眼表达TGFβ2和VIP蛋白上调（P〈0.05）、TH蛋白下调（P〈0.05）。与正常对照眼、自身对照眼比较,遮盖眼视网膜Müller细胞分泌DA减少。结论Müller细胞是视网膜近视信号因子TGFβ2、VIP和DA的一个重要来源。在近视发生过程中Müller细胞可能通过合成、分泌这些近视信号因子,参与近视发生的调控。     

豚鼠形觉剥夺性近视眼视网膜、脉络膜多巴胺代谢的变化

目的研究形觉剥夺对豚鼠神经视网膜、视网膜色素上皮（retinal pigment epithelium,RPE）／脉络膜复合体多巴胺（dopamine,DA）代谢的影响。方法28日龄豚鼠36只,分为3组：正常对照组、遮盖组、遮盖＋去遮盖组,每组12只。遮盖组用半透明眼罩遮盖豚鼠右眼14d,遮盖＋去遮盖纽在遮盖11d后去遮盖3d。14d后测定角膜曲率半径、眼球屈光度和眼轴长度。处死豚鼠,取眼后极部视网膜、脉络膜组织,用免疫组化染色和Western blotting法检测酪氨酸羟化酶（tyrosine hydroxylase,TH）蛋白在神经视网膜、RPE／脉络膜复合体的表达情况,用高效液相色谱检测神经视网膜、RPE／脉络膜复合体的DA、二羟基苯乙酸（3,4-dihydroxyphenylacetic acid,DOPAC）的含量。结果TH蛋白阳性表达于视网膜神经节细胞和内核层部分细胞,RPE／脉络膜复合体中表达阴性。遮盖14d后,豚鼠遮盖眼眼轴延长,近视形成,神经视网膜TH蛋白表达量和DA、DOPAC含量降低（P〈0．05）。遮盖＋去遮盖纽的遮盖眼近视程度低于遮盖组．其神经视网膜TH蛋白表达量和DA、DOPAC含量升高（P〈O．05）,但仍低于正常对照组（P〈O．05）。各纽豚鼠RPE／脉络膜复合体的DA、DOPAC含量比较,差异无统计学意义（P〉0．05）。结论形觉剥夺能调控豚鼠神经视网膜DA代谢,但不影响RPE／脉络膜复合体的DA代谢。     

左旋多巴对豚鼠形觉剥夺性近视形成的影响

目的研究腹腔注射左旋多巴（L-dopa）对豚鼠形觉剥夺性近视眼屈光状态及视网膜多巴胺含量的影响。方法眼罩遮盖建立豚鼠形觉剥夺性近视眼模型,分为正常对照组、L—dopa组（10mg／kg）、生理盐水组、遮盖组、遮盖＋L-dopa组、遮盖＋生理盐水组6个组。遮盖10d后,测定角膜曲率半径、眼球屈光度和眼轴长度,高效液相色谱检测视网膜多巴胺含量。结果眼罩遮盖10d后,豚鼠遮盖眼眼轴延长、近视形成,视网膜多巴胺含量降低（P〈0．05）,但角膜曲率半径无明显变化。腹腔注射L-dopa引起遮盖眼视网膜多巴胺含量增加、近视程度减轻（P〈0．05）,但对正常豚鼠眼球的屈光发育无明显影响（P〉0．05）。腹腔注射生理盐水后,豚鼠眼球屈光状态和视网膜多巴胺含量无明显变化（P〉0．05）。结论腹腔注射L—dopa能通过补充遮盖眼视网膜多巴胺含量,抑制豚鼠形觉剥夺性近视的形成。     

豚鼠近视眼视网膜Müller细胞近视因子基因的表达

目的 研究视网膜近视因子基因在原代培养的豚鼠近视眼视网膜Müller细胞中的表达变化.方法 3～4周龄断乳三色豚鼠40只,取20只建立近视眼模型(以右眼作为实验眼,以对侧未遮盖眼作自身对照),剩余的20只豚鼠作正常对照.用眼罩遮盖法建立豚鼠近视眼模型,用酶消化法原代培养其视网膜Müller细胞.RT-PCR检测酪氧酸羟化酶(tyrosine hydroxylase,TH)、诱导型一氧化氙合成酶(inducible nitric oxide synthase,iNOS)、神经型一氧化氮合成酶(neu-ronal nitric oxide synthase,nNOS)、内皮型一氧化氮合成酶(endothelial nitric oxide synthase,eNOS)、视黄醛脱氢酶(retinaldehyde dehydrogenase,RALDH)、醛脱氢酶(aldehyde dehydrogenase,ALDH)、碱性成纤维细胞生长因子(basic fi-broblast growth factor,bFGF)、转化生长因子β(transforming growth factor-β,TGF-β)的mRNA在正常对照眼、自身对照眼和近视眼视网膜Müller细胞中的表达情况.数据分析采用One-way ANOVA检验.结果 眼罩遮盖10 d后,遮盖眼眼轴延长,近视形成.酶消化法成功培养出视网膜Müller细胞.正常对照眼、自身对照眼和遮盖眼视网膜Müller细胞均阳性表达nNOS、bFGF、TH、TGF-B mRNA,且遮盖眼表达nNOS、bFGF和TGF-B mRNA上调(P<0.05),TH mRNA下调(P<0.05).iNOS mRNA仅在遮盖眼视网膜Müller细胞阳性表达.三组视网膜Müller细胞均不表达eNOS、RALDH和ALDH mRNA.结论 豚鼠近视眼视网膜Müller细胞表达nNOS、iNOS、bFGF和TGF-B mRNA上调,TH mRNA下调.Müller细胞是近视眼视网膜信号因子一氧化氮(nitric oxide,NO)、多巴胺(dopamine,DA)、bFGF和TGF-β的一个重要来源.     

豚鼠近视眼视网膜Müller细胞近视因子基因的表达

目的 研究视网膜近视因子基因在原代培养的豚鼠近视眼视网膜Müller细胞中的表达变化.方法 3～4周龄断乳三色豚鼠40只,取20只建立近视眼模型(以右眼作为实验眼,以对侧未遮盖眼作自身对照),剩余的20只豚鼠作正常对照.用眼罩遮盖法建立豚鼠近视眼模型,用酶消化法原代培养其视网膜Müller细胞.RT-PCR检测酪氧酸羟化酶(tyrosine hydroxylase,TH)、诱导型一氧化氙合成酶(inducible nitric oxide synthase,iNOS)、神经型一氧化氮合成酶(neu-ronal nitric oxide synthase,nNOS)、内皮型一氧化氮合成酶(endothelial nitric oxide synthase,eNOS)、视黄醛脱氢酶(retinaldehyde dehydrogenase,RALDH)、醛脱氢酶(aldehyde dehydrogenase,ALDH)、碱性成纤维细胞生长因子(basic fi-broblast growth factor,bFGF)、转化生长因子β(transforming growth factor-β,TGF-β)的mRNA在正常对照眼、自身对照眼和近视眼视网膜Müller细胞中的表达情况.数据分析采用One-way ANOVA检验.结果 眼罩遮盖10 d后,遮盖眼眼轴延长,近视形成.酶消化法成功培养出视网膜Müller细胞.正常对照眼、自身对照眼和遮盖眼视网膜Müller细胞均阳性表达nNOS、bFGF、TH、TGF-B mRNA,且遮盖眼表达nNOS、bFGF和TGF-B mRNA上调(P<0.05),TH mRNA下调(P<0.05).iNOS mRNA仅在遮盖眼视网膜Müller细胞阳性表达.三组视网膜Müller细胞均不表达eNOS、RALDH和ALDH mRNA.结论 豚鼠近视眼视网膜Müller细胞表达nNOS、iNOS、bFGF和TGF-B mRNA上调,TH mRNA下调.Müller细胞是近视眼视网膜信号因子一氧化氮(nitric oxide,NO)、多巴胺(dopamine,DA)、bFGF和TGF-β的一个重要来源.     

形觉剥夺性近视豚鼠视网膜中神经生长因子及其受体的表达

目的 探讨视网膜神经生长因子（NGF）及其受体（TrkA）在豚鼠形觉剥夺性近视（FDM）视网膜中的表达.方法 对出生7 d豚鼠以半透明眼罩遮盖右眼2个月制备FDM动物模型,左眼作为对照.遮盖前及遮盖2、4、8周后,检影验光检测双眼屈光度,A型超声测量双眼眼轴长度.免疫组织化学和逆转录一聚合酶链式反应（RT-PCR）检测视网膜NGF和TrkA的表达变化.结果 形觉剥夺使豚鼠眼轴增长,近视屈光度增加,遮盖眼与对照眼相比屈光度差异有统计学意义（P＜0.01）.遮盖眼NGF与TrkA免疫活性逐渐降低,NGF与TrkAmRNA表达下调,与对照组比较差异有统计学意义（P＜0.01）.结论 NGF和TrkA可能参与调控FDM的形成.     

N-甲基-D-天冬氨酸受体1在形觉剥夺性近视豚鼠视网膜上的表达

目的对豚鼠行形觉剥夺建立近视动物模型，观察离子型谷氨酸受体N-甲基-D-天冬氨酸受体1（N—methyl—D—aspartate receptor 1．NMDAR1）在近视豚鼠视网膜上的动态表达．探讨其在近视发病机制中的作用。方法60只三色豚鼠随机分为3组：未遮盖组（Ⅰ）、单眼遮盖2周组（Ⅱ）、单眼遮盖3周组（Ⅲ），其中右眼遮盖为实验眼，左眼为自身对照眼。对各组进行视网膜检影和A超测眼轴。分别运用免疫组化及Western Blotting法检测各组豚鼠视网膜NMDAR1蛋白表达。结果Ⅰ组双眼呈轻度远视状态．双眼眼轴差异无显著性（P〉0．05）；Ⅱ组实验眼呈轻度近视（-1.583±1.478）D，自身对照眼呈轻度远视（2.500±1.017）D：实验眼眼轴较自身对照眼轻度延长（P〈0．05）；Ⅲ组实验眼呈中度近视（-3．417±l.169）D，自身对照眼呈轻度远视（1.813±1．072）D；实验眼眼轴较自身对照眼明显延长（P〈0．05）。免疫组化显示NMDAR1主要表达在豚鼠视网膜的内核层细胞及神经节细胞。Ⅰ组实验眼视网膜上NMDAR1蛋白含量为0．338±0．314．Ⅱ组实验眼NMDAB1蛋白含量升高为0．464±0．280．Ⅲ组实验眼视网膜NMDAR1蛋白含量明显上调为0．635±0．037;实验眼视网膜上NMDAR1蛋白含量随遮盖时间延长明显上调．与自身对照眼比较差异有显著性（P〈0．05）。结论形觉剥夺可明显上调豚鼠视网膜NMDAR1的蛋白表达，形觉剥夺产生的异常视觉信号可能通过刺激谷氨酸的释放、NMDAR1过度生成，参与近视的调控。     

Exogenous levodopa increases the neuro retinal dopamine of Guinea pig myopic eyes in vitro

 Purpose:In our previous work, it has been shown that intraperitoneal injection of L-DOPA can inhibit the development of occlusion myopia in guinea pigs, and increase levels of retinal dopamine. The aim of this study was to investigate whether exogenous L-DOPA can be converted into dopamine in cultured retina of guinea pig eyes subjected to visual deprivation, and to evaluate whether müller cells are involved in the processing of retinal dopamine induced by L-DOPA. Methods:Fifty-eight guinea pigs were randomly divided into 2 groups at the age of 4 weeks: normal control and visual deprivation. Form deprivation was induced with translucent eye shields over the right eye, and lasted for ten days. Corneal curvature, refraction and axial length were measured in all animals. In vitro, neuro-retina and müller cell were cultured, and L-DOPA was added to the culture medium at three concentrations: 1μM, 10μM and 100μM. Subsequently, dopamine content was evaluated by high-performance liquid chromatography, and apoptotic cells were identified by TUNEL staining. Results:Ten days of occlusion caused the affected eyes to elongate and become myopic in guinea pigs. Compared with the deprivation group, 10цM L-DOPA treament significantly raised dopamine content in cultured retina and müller cells (P<0.05). However, 1μM and 100μM L-DOPA treatment caused no increase in dopamine levels (P>0.05). Apoptotic nuclei were detected in the ganglion cell layer (92.5%±8.3%) and inner nuclear layer (46.8%±9.1%) of cultured retina treated with 100 μM L-DOPA. Moreover, 100 цM L-DOPA also caused apoptosis of retinal müller cells, at a mean rate of 59.4 ±11.3%. Conclusion:Our results suggest that exogenous L-DOPA can cause an increase in retinal dopamine in form-deprived guinea pig eyes in vitro, and that müller cells are involved in the increase in retinal dopamine.     

Dynamic changes of ocular biometric parameters: a modified form-deprivation myopia model of young guinea pigs

AIM: To evaluate the dynamic ocular biometric changes of a modified form-deprivation myopia model in young guinea pigs. METHODS: The animals were randomly assigned to two groups: the monocularly deprived facemask group (MDF, with all the right eyes covered, n=24) and the normal control group(free of facemask, n=24). Each group was then equally divided into four subgroups which were followed up for 2, 4, 6 and 8 weeks, respectively. Parameters measured from every eye included refraction, corneal curvature, axial length and the dry weight of sclera at the posterior pole. RESULTS: All the facemasks remained in place during the follow-up. The covered eyes developed myopia with the vitreous chamber lengthening and the dry weight of posterior sclera reduced at each time point compared with the contralateral uncovered(P<0.05 at all time points). The changes had a linear correlation with the deprivation time (P<0.05). There were no significant differences in all the parameters between the uncovered eyes of MDF group and the normal control group (P>0.05 at all time points). CONCLUSION: Monocular form deprivation with the facemask is highly effective and non-invasive in inducing axial myopia in guinea pigs. The axial myopia is mainly caused by the increased vitreous chamber length and the weakened posterior sclera rigidity. The form-deprivation eye didn't interfere with the natural development of the contralateral eye.     

Dynamic changes of ocular biometric parameters:a modified form-deprivation myopia model of young guinea pigs

AIM:To evaluate the dynamic ocular biometric changes of a modified form-deprivation myopia model in young guinea pigs.METHODS:The animals were randomly assigned to two groups:the monocularly deprived facemask group(MDF,with all the right eyes covered,n =24) and the normal control group(free of facemask,n =24).Each group was then equally divided into four subgroups which were followed up for 2,4,6 and 8 weeks,respectively.Parameters measured from every eye included refraction,corneal curvature,axial length and the dry weight of sclera at the posterior pole.RESULTS:All the facemasks remained in place during the follow-up.The covered eyes developed myopia with the vitreous chamber lengthening and the dry weight of posterior sclera reduced at each time point compared with the contralateral uncovered(P <0.05 at all time points).The changes had a linear correlation with the deprivation time(P <0.05).There were no significant differences in all the parameters between the uncovered eyes of MDF group and the normal control group(P >0.05 at all time points).CONCLUSION:Monocular form deprivation with the facemask is highly effective and non-invasive in inducing axial myopia in guinea pigs.The axial myopia is mainly caused by the increased vitreous chamber length and the weakened posterior sclera rigidity.The form-deprivation eye didn’t interfere with the natural development of the contralateral eye.     

不同浓度阿托品滴眼液对豚鼠形觉剥夺性近视的影响

目的探讨不同浓度阿托品滴眼液对单眼形觉剥夺幼年豚鼠的屈光发育的影响,并分析阿托品抑制近视的可能作用位点和机制。方法实验研究。将80只3周龄体质量在100 g左右的豚鼠随机分至5组：单眼形觉剥夺4周组（8只）、形觉剥夺加点药同时进行4周组（每个浓度各8只）、形觉剥夺2周后再加点药2周组（每个浓度各8只）、单纯点药4周组（每个浓度各6只）、空白对照组（6只）。阿托品粉剂溶于单蒸水配制成3个浓度的阿托品滴眼液：0.2%、1.0%、3.0%。每天早上8∶30-9∶00间点药。在实验前、实验2 周、实验4 周时测量各组豚鼠屈光力、角膜曲率、眼轴长度等相关生物学参数。实验4周结束后取豚鼠眼视网膜做冰冻切片,免疫荧光法标记豚鼠视网膜上表达胰高血糖素的细胞。采用配对样本t检验和重复测量的双因素方差分析进行数据分析。结果单纯形觉剥夺组,实验2周后实验眼屈光度较自身对照眼往近视方向发展,同时伴有玻璃体腔加深、眼轴延长,差异有统计学意义（t=-11.09、7.89、3.73,P<0.05）;4周后,差异更显著。形觉剥夺加点药同时进行的3个浓度组,实验2周后实验眼与自身对照眼的各屈光参数差异均无统计学意义,而2眼差值与单纯剥夺组比较,屈光度、玻璃体腔深度、眼轴长度差异均有统计学意义（F=26.335、6.479、6.910,P<0.05）;4周后,3个浓度组实验眼屈光度与自身对照眼比较均开始往近视方向发展,差异有统计学意义（t=-4.67、-7.54、-2.78,P<0.05）,同时玻璃体腔加深,眼轴延长,而2眼差值与单纯剥夺组比较,各屈光参数的差异仍有统计学意义（F=16.962、5.193、6.882,P<0.05）;但3个浓度组的组间两两比较显示,各参数实验前后差异无统计学意义。形觉剥夺2周后再加点药2周组,实验4周后各浓度组2眼差值与单纯剥夺4周组比较,各屈光参数差异均无统计学意义。各组豚鼠视网膜上均未标记出胰高血糖素表达阳性的细胞。结论在3%的浓度范围内,阿托品滴眼液能通过抑制玻璃体腔加深、眼轴延长从而部分抑制豚鼠形觉剥夺性近视的发生,且作用效果没有明显的浓度依赖性。但在近视形成后运用阿托品,并不能抑制近视的进展。胰高血糖素能途径没有参与阿托品对豚鼠近视发生发展的作用过程。     

Modulation of TGFβ2 and dopamine by PKC in retinal Müller cells of guinea pig myopic eye

AIM: To investigate the effect of protein kinase C (PKC) on transforming growth factor-β2 (TGFβ2) and dopamine in retinal Müller cells of guinea pig myopic eye. METHODS: Myopia was induced by translucent goggles in guinea pig, whose retinal Müller cells were cultured using the enzyme-digesting method. Retinal Müller cells were divided into 5 groups: normal control, myopia, myopia plus GF109203X, myopia plus PMA, myopia plus DMSO. PKC activities were detected by the non-radioactive methods. TGFβ2 and tyrosine hydroxylase (TH) proteins were analyzed by Western Blotting in retinal Müller cells. Dopamine was determined by the high-performance liquid chromatography- electrochemical detection in suspensions. RESULTS: After 14 days deprived, the occluded eyes became myopic with ocular axle elongating. Müller cells of guinea pigs were obtained using enzyme digestion. Compared with normal control group, the increase in PKC activity and the up-regulation in TGFβ2 expression were found in retinal Müller cells of myopic eyes, with the decrease of TH and dopamine content (P <0.05). After PKC activated by PMA, TGFβ2 and TH content were up-regulated with the increase of dopamine content (P <0.05). While the PKC activities was inhibited by GF109203X, proteins of TGFβ2 and TH were down-regulated in the myopic eyes, with the decrease of dopamine content (P <0.05). CONCLUSION: TGFβ2 and dopamine are modulated by PKC in Müller cells of the myopic eyes in guinea pig.     

哌仑西平滴眼液治疗豚鼠形觉剥夺性近视

目的研究眼表局部使用选择性M1受体拮抗剂哌仑西平(pirenzepine,以下简称PIR)后对豚鼠形觉剥夺性近视眼的治疗作用及药物对眼部的刺激性和耐受性,探讨其临床应用前景。方法①药效学研究选取3周龄豚鼠10只,均右眼行眼睑缝合,左眼开放。随机分为两组:实验组(5只)右眼滴2%PIR滴眼液,对照组(5只)右眼滴0.9%氯化钠溶液。4周后检查屈光度数变化及眼轴长度,评价药效。②药物刺激性研究选取新西兰白兔8只,均左眼给2%PIR滴眼液,右眼给0.9%氯化钠溶液。分为两组:单次给药组一次性给药100μl后连续观察3 d;重复给药组连续给药8d,停药后再连续观察7 d。实验结束后摘除眼球做组织切片光镜检查。结果右眼遮盖4周后,0.9%氯化钠溶液组诱导出-2.1 D的相对近视(t=3.5,P<0.05),2%PIR滴眼液组屈光度变化差异无显著性(P>0.05)。2%PIR组实验前后眼轴长度变化差异也无显著性(P>0.05)。单次给2%PIR组在给药1 h后的评分与给药前相比差异有显著性(t=3.46,P<0.05),其余观察点的评分与给药前相比差异均无显著性。重复给药组实验前后的评分差异也无显著性(P>0.05)。组织学检查未发现明显的毒性反应。结论哌仑西平滴眼液能够有效抑制豚鼠形觉剥夺性近视的发展,眼部刺激性小、耐受性好,无明显眼部毒性反应。     

Basic fibroblast growth factor suppresses retinal neuronal apoptosis in form-deprivation myopia in chicks

PURPOSE: Chorioretinal atrophy including retinal neuronal apoptosis occurred in chronic form-deprivation myopia induced by lid suture in chicks. We investigated whether exogenous basic fibroblast growth factor (bFGF) could simultaneously inhibit the excessive axial elongation and retinal neuronal loss in the myopic chick eyes. METHODS: Unilateral form deprivation was produced in neonatal male Hyline chicks by lid suture 24 hr after hatching. Ten microliters of solution containing 5 ng bFGF or PBS (vehicle) was injected into the vitreal chamber at 10 weeks of age, once every 3 days until week 12, when the animals were sacrificed. Ocular refraction and axial length were assessed by retinoscopy and calipers at the age of 12 weeks. Retinal apoptotic neurons and their caspase-3-like protease activity were analyzed by transmission electron microscopy, the terminal-deoxynucleotidyl transferase-mediated biotin-deoxyuridine triphosphate nick-end labeling (TUNEL) staining, and a colorimetric method using Ac-DEVD-pNA as a substrate. The number of TUNEL-positive cells was counted to analyize the survival activity of bFGF on retina. RESULTS: After 12 weeks of lid suture, the control eyes were either emmetropic or hyperopic, whereas the deprived eyes became myopic with axial length increased. TUNEL-positive nuclei, condensed nuclear chromatin, and apoptotic bodies were observed in posterior retinal outer nuclear layer (ONL) and inner nuclear layer (INL) in the myopic chick eyes. Activity of retinal caspase-3-like protease in these eyes was elevated. In addition to ameliorating myopic ocular growth, intravitreal bFGF therapy significantly reduced the number of retinal apoptotic neurons and downregulated caspase-3 activity. CONCLUSIONS: Exogenous bFGF effectively ameliorates the excessive axial elongation and retinal neuron apoptosis in chronic form-deprivation myopia in chicks. It is possible that bFGF will be a promising therapeutic agent for high human myopia.