低氧条件下大鼠视网膜葡萄糖调节蛋白的表达

EXPRESSION OF GLUCOSE REGULATED PROTEIN IN RAT RETINA UNDER HYPOXIA

目的研究低氧条件下葡萄糖调节蛋白(grp78)在大鼠视网膜中的表达情况,探讨内质网应激在视网膜低氧条件下的作用及其机制。方法Wistar大鼠30只,随机分为正常对照组和实验组,正常对照组饲养于常氧环境中,实验组饲养于低氧仓。实验组又按照在低氧仓饲养时间分为6、12、24、48和72h等5个亚组,并于这5个时间点处死大鼠,摘除眼球,应用免疫组织化学方法和RT-PCR法测定各组大鼠grp78蛋白表达。结果grp78在正常大鼠视网膜中少量表达,低氧条件下6h开始升高,24h到达高峰,72h降至正常水平。低氧条件下6、12、24、48h表达量与正常对照组比较差异有显著性(F=32.22,q=5.32～11.53,P<0.05);72h视网膜grp78的表达与正常对照组相比,差异无显著性(q=2.79,P>0.05)。结论低氧条件下grp78在大鼠视网膜中表达,它参与了大鼠视网膜低氧损伤的发生机制。

Objective To investigate the expression of glucose regulated protein （grp78） under hypoxia and to study the effect and mechanism of endoplasmic reticulum stress. Methods Thirty wistar rats were randomly divided into normal control group and experimental group. The rats in the experimental group were killed after hypoxia breeding for 6, 12, 24, 48 and 72 hours, respectively the eyeballs were then removed. The expression of grp78 was studied immunohistochemically and by using reverse transcriptase PCR （RT-PCR）. Results Expression of grp78 was weak in normal retina, but increased after 6 hours of hypoxia, reached its peak after 24 hours of hypoxia and fell back to the normal level after 72 hours. The differences in expressions of grp78 in the rats after hypoxia breeding for 6, 12, 24 and 48 hours were significant, compared with that of control group （F= 32.22 q= 5.32--11.53 P〈0.05）. The difference between breeding of 72 h group and the control group was not significant （q= 2.79,P〈0.05）. Conclusion grp78 is strongly expressed in rat retina under hypoxia and involves in the mechanism of retinal hypoxic injury.