Expression Of HIC-5 In Rat Model Of Glucocorticoid-induced Ocular Hypertension

Objective: Establish a rat model of glucocorticoid-induced ocular hypertension,to observe the changes of HIC-5 expression in the rat model of glucocorticoid-induced ocular hypertension,and to explore the role of HIC-5 in the pathogenesis of glucocorticoid induced glaucoma.Methods: Ninety male SD rats were randomly divided into dexamethasone group(40rats),sterile water group(25rats)and blank control group(25rats).Right eye of the dexamethasone group rats were subconjunctival injected with dexamethasone injection 0.2m L(5mg/m L)once every other day,and the right eye of the sterile water group was subconjunctival injected with 0.2mL sterile water every other day,blank control group without any treatment.The intraocular pressure(IOP)was measured before and after conjunctival injection using a rebound-type tonometer.The rats were executed after 30 days and the expression of HIC-5 in the anterior chamber angle and its surrounding tissues was detected by immunofluorescence and Western-blot.Results: A total of 21 eyes in the dexamethasone group were successfully induced to the model of glucocorticoid induced glaucoma,sign as model group.Randomly select 21 rats from the sterile water group and blank control group,sign as sterile water group and blank control group.There was no statistically significant difference between three groups in IOP before and after treatment,and the normal IOP was 10.65 ± 0.53 mmHg.In model group,the IOP began to increase on the 8 day after the right eye treatment.On the day of 8-16,the IOP continued to increase,and then reached a stable state at the end of the 24 day.Before and after treatment there was no significant difference in IOP in sterile water group.In the frozen sections of rats,the trabecular meshwork,iris ciliary body,Schlemm tube and other anterior chamber angle structure can be observed.Compared with sterile water group and blank control group,the fluorescence intensity of HIC-5 in the anterior chamber angle and its surrounding tissue was significantly increased after treatment with dexamethasone in modle group,and the difference was statistically significant(F=220.06,P < 0.01).Western blot showed that the expression of HIC-5 in modle group was significantly higher than that in sterile water group and blank control group(F=27.62,P<0.01).Conclusion: The model of glucocorticoid-induced ocular hypertension can be successfully produced by subconjunctival injection of dexamethasone in rats.The expression change of HIC-5 in the rat model of glucocorticoid-induced ocular hypertension may be related to the occurrence of glucocorticoid-induced ocular glaucoma.