ABSTRACT
AIM:To remark the effect of Qingguang'an Ⅱ on expression of PAX6, Ngn1, and Ngn2 mRNA of rats with chronic high intraocular pressure.METHODS:Totally 40 male SD rats were randomly divided into 6 groups, that was:A:blank group, B:model group, C:Qingguang'an Ⅱ low dose group, D:Qingguang'an Ⅱ moderate dose group, E:Qingguang'an Ⅱ high dose group, F:Yimaikang disket group.B, C, D, E, F groups of experimental rats were established the model of chronic high intraocular pressure (IOP) by cauterizing of superficial scleral vein.Animal model was established successfully by using monitoring IOP consistently keep above 25mmHg for 8wk as cut-off criterion.Tissues of Eyes were obtained after intragastric administration for 2wk and 4wk.The expressions of PAX6, Ngn1, and Ngn2 mRNA were investigated by Real-time PCR.RESULTS:At the time-point of 2wk, PAX6, Ngn1, and Ngn2 mRNA in group B were statistically expressed in lower level comparing with other groups (P0.05).CONCLUSION:In summar, Qingguang'an Ⅱ and Yimaikang disket can remarkably increase the expressions of PAX6, Ngn1, and Ngn2, which suggest protecting the optic nerve of rats caused by chronic high IOP.What's more, this study indicated that, in the protection of optic nerve of rats with chronic high IOP, the high dose of Qingguang'an Ⅱ at the time-point of 4wk was the better choice.
ABSTRACT
Background Our previous study showed that the expression level of glial fibrillary acid protein (GFAP) increases in astrocytes and Müller cells of retina in chronic hypertensive eye,and this change was clarified to be associated with the damage process of the retinal ganglion cells (RGCs).Aquaporin 4 (AQP4) exists in neural glial cells,so we conjecture AQP4 plays a role in the regulating GFAP expression in glaucomatous eye.Objectives This study was to investigate whether AQP4 gene can regulate the expression of GFAP in retina and explore the effect of AQP4 on RGCs damage of glaucoma.Methods Chronic ocular hypertensive eye models were established by cauterizing the scleral venous in the left eyes of 30 male AQP4-/-mice and 30 male wild type (WT) mice with the same background,and the right eyes served as control eyes.The intraocular pressure (IOP) was measured with Icare rebound tonometer at 1 day,3,7,14 and 28 days respectively and the retinas were isolated from 6 of each types of mice at the corresponding time points.The expression of GFAP in the retina was detected by Western blot.The use and care of the experimental animals followed ARVO Statement.Results The IOP was significantly higher in the model eyes than that of the control eyes 1 day,3,7,14 and 28 days in both AQP-/-mice (t =15.29,16.02,13.77,14.34,12.40,all at P＜0.05) and WT mice (t =17.65,14.91,15.97,13.41,12.53,all at P ＜0.05).GFAP was expressed in the control eyes both of the AQP4-/-mice and the WT mice.The expressing level of GFAP (GFAP/β-actin) in retinas was 1.00±0.00,1.99±0.29,4.05±0.69,4.47±0.48,3.21±0.35 and 3.25±0.53 in the control eyes and 1-,3-,7-,14-,28-day model eyes of WT mice; and those in the AQP4-/-mice were 1.00±0.00,1.69±0.31,2.27 ±0.55,2.79 ± 0.39,1.93 ± 0.31 and 1.54 ± 0.40,with a significant difference in the expressing level of GFAP in various time points (F =9.54,P＜0.05).In addition,significant gradually elevation of GFAP expression were seen in the WT mice and gradually decline of GFAP expression was found in the AQP4-/-mice with the lapse of time (all at P＜0.05).No significant difference was seen in the expression of GFAP in the control eyes between the WT mice and AQP4-/-mice (P＞0.05).However,the expression level of GFAP in retina was significantly higher in the WT mice than that of A QP4-/-mice 3,7,14 and 28 days after operation (t =4.51,7.95,6.12,5.76,all at P＜0.01).tonelusions In chronic high IOP mice,AQP4 gene plays an important role in retinal damage by upregulating the expression of GFAP in retina and promoting the activation of RGCs.AQP4 probably is a new target of treatment of glaucoma.