方法：将40只80眼雄性SD大鼠随机分成6组，分别为：A组(空白组)、B组(模型组)、C组(青光安Ⅱ号方低剂量组)、D组(青光安Ⅱ号方中剂量组)、E组(青光安Ⅱ号方高剂量组)、F组(益脉康分散片组)。将B、C、D、E、F五组实验大鼠采用烧灼巩膜表浅静脉法建立大鼠慢性高眼压模型，术后监测眼压，使眼压维持在25mmHg以上持续2mo视为慢性高眼压造模成功。动物维持高眼压状态2mo后开始灌胃，灌胃后2、4wk分别处死，qPCR检测PAX6、Ngn1、Ngn2 mRNA的相对表达量。

结果：PCR结果显示：SD大鼠慢性高眼压模型成模灌胃2wk后，各组PAX6、Ngn1、Ngn2 mRNA表达量与B组比较，差异有统计学意义(P<0.05)； C、D、E、F组组间比较，差异无统计学意义(P>0.05)。SD大鼠慢性高眼压模型成模灌胃4wk后，C、D、E组与F组比较，差异有统计学意义(P<0.05)。C、D组与E组比较，差异有统计学意义(P<0.05)。C组与D组比较，差异无统计学意义(P>0.05)。

结论：青光安Ⅱ号方及益脉康分散片均能增加PAX6、Ngn1、Ngn2 mRNA的相对表达量，对慢性高眼压大鼠视网膜神经节细胞有一定的保护作用； 在对慢性高眼压大鼠视神经的保护中，青光安Ⅱ号方高剂量灌胃后4wk时效果最优。

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(P<0.05). Moreover, at the time-point of 4wk, PAX6, Ngn1, and Ngn2 mRNA in group C, D and E were statistically expressed in higher level comparing with group F(P<0.05). Besides, PAX6, Ngn1, and Ngn2 mRNA in group C and D were statistically expressed in lower level comparing with group E(P<0.05). PAX6, Ngn1, and Ngn2 mRNA in group C and D were expressed in similar level(P>0.05).

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.