高眼压及持续时间对大鼠视网膜caspase-3表达的影响

目的研究高眼压及其持续时间对大鼠视网膜caspase-3表达的影响。方法通过前房灌注平衡盐液建立大鼠急性高眼压模型:高眼压持续时间均为4h,依据眼内压的不同将SD大鼠60只随机分为正常对照组、40mm Hg(1mm Hg=0.133kPa)组、60mm Hg组、80mm Hg组、100mm Hg组,每组12只。将眼内压为80mm Hg的48只SD大鼠随机分为正常对照组、2h组、4h组、8h组,每组12只。正常对照组不给予前房灌注,其他各组分别给予不同的高眼压或高眼压持续不同时间。各组灌注结束后快速摘除眼球,分别采用Western印迹法和免疫组织化学法检测视网膜caspase-3的表达。结果与对照组相比,40mm Hg组大鼠视网膜caspase-3的表达无增加(P>0.05);60mm Hg组、80mm Hg组和100mm Hg组大鼠视网膜caspase-3的表达均强于正常对照组(q值分别为4.87、5.28和6.71;P<0.01),但各组之间差异无统计学意义(P>0.05)。与对照组相比,2h组大鼠视网膜caspase-3的表达差异无统计学意义(P>0.05),4h组和8h组大鼠视网膜caspase-3的表达均增加(q值分别为2.81和3.67;P<0.01)。表达caspase-3的视网膜细胞主要位于神经节细胞层、外丛状层和内丛状层。结论采用前房灌注平衡盐液制作急性高眼压模型研究高眼压大鼠视网膜caspase-3的表达时,眼内压为80mm Hg、高眼压持续4h即可。

Effect of intraocular hypertension and its duration on the expression of caspase.3 in rat retina

Objective To investigate the effect of intraocular hypertension and its duration on the expression of caspase-3 in rat retina. Methods Forty-eight rats of acute intraocular hypertension, induced by infusion of balanced salt solution into anterior chamber, were divided into four groups randomly. The intraoeular pressure were 40 mm Hg, 60 mm Hg, 80 mm Hg and 100 mm Hg with the same duration （4 hours） respectively; twelve additional rats were took as normal control group. Thirty-six rats of acute intraocular hypertension induced in the same way were divided into three groups randomly. The durations of intraocular hypertension （80 mm Hg） were 2 hours, 4 hours and 8 hours respectively; twelve additional rats were took as normal control group. The level and location of caspase-3 protein were checked by Western-blot analysis and immunohistochemistry respectively. Results The level of caspase-3 protein in dO mm Hg group was not significantly higher than that in normal control group （P 〉 0.05 ）, but in 60, 80 and 100 mm Hg group （q =4.87,5.28,6.71 ; P 〈0.01 ）. The difference among 60,80 and 100 mm Hg group was not significant （P 〉0.05）. The level of caspase-3 protein in 2 h group was not significantly higher than that in normal control group, but both in 4 h group and 8 h group （q = 2.81,3.67 ; P 〈 0.01 ）. Immunohistochemistry showed that the expression of caspase-3 protein was mainly located in ganglion cell layer, outer plexiform layer and inner plexiform layer. Conclusions Intraocular pressure with 80 mm Hg and duration of 4 hours should be effective to induce the expression of caspase-3 in rat retina.