三种热休克蛋白mRNA在高眼压大鼠视网膜中的表达

Expression of heat shock protein mRNA in rat retina with ocular hypertension

目的探讨热休克蛋白家族（HSPs）中HSP27、HSP70和HSP90 mRNA在高眼压大鼠视网膜中的表达水平,及其与青光眼视神经病变可能的潜在关系。方法将30只Wistar大鼠随机分为高眼压组和伪手术对照组（各15只）,右眼为实验眼,左眼为对照眼。采用双极水下电凝器电凝大鼠右眼巩膜表面3组静脉的方法建立高眼压动物模型,用Tonopen眼压计检测眼压,每周2次。高眼压组眼压保持在27-35mmHg;对照组为12-17mmHg。分别于第10、20、60d处死大鼠,摘除眼球,剥离视网膜,提取RNA,Northern印迹分析。结果Northern印迹分析显示：在眼压升高第10、20、60d,视网膜HSP27的mRNA水平平均增高达250%,HSP70和HSP90的mRNA水平平均增高达98%和82.6%,HSP27水平明显增高,HSP70,HSP90变化不大。结论高眼压大鼠视网膜HSP27 mRNA表达水平持续增高,推测与高眼压状态下视网膜神经节退变有潜在关系。

Objective Studies showed that expression of HSPs is up-regulated in cellular stress reaction,but its expression in glaucomatous optic neuropathy is unclear.Focus of present study was to detect the changes of expression of heat shock protein（HSP27,HSP70 and HSP90） mRNA in retina of rat with ocular hypertension and explore the potential relationship between HSPs with glaucomatous optic neuropathy.MethodsOcular hypertention model was established in the right eyes of 15 Wistar rats by bipolar electrocoagulation condensate 3 episcleral and limbal veins,and other right eyes of 15 Wistar rats were as sham control group.The left eyes of all animals were assigned to blank control group.Intraocular pressure（IOP） was monitored twice weekly with Tonopen.In the model eyes,IOP ranged from 27 to 35 mmHg throughout the study period.In sham control eyes,IOP ranged from 12 to 17mmHg.Rats were euthanized at 10,20,or 60 days following the induction of ocular hypertension,and RNA were isolated from retina dissected free.Northern blot analysis was used to detect mRNA expressions of HSP27,HSP70,HSP90 rat retina.ResultsNorthern blot analysis demonstrated that compared with sham goup, expression of HSP27 mRNA in the retina showed a dynamic increase on 10,20 and 60 days following the induction of ocular hypertension with a mean elevated percentage of 250% in model group,and expression of HSP70,HSP90 mRNA followed a parallel pattern with a mean elevated percentage of 98% and 82.6%,respectively.No significant change was found in HSP70 protine expression.ConclusionThe mRNA level of HSP27 is upregulated in retina of Wistar rats with ocular hypertension.There may be a potential relationship between the upregulation of HSP27 and degeneration of retinal ganglion cells in hypertension eyes.