外源性视黄酸对鸡后巩膜基质MMP-2表达作用的动态观察

Influence of ectogenesis retinoic acid on expression of MMP-2 in chick eyes

注射后随时间延长眼轴及屈光度逐渐增加,不同时间组间差异极显著(P<0.01),MMP-2mRNA表达上调,不同时间组间差异无显著性(P>0.05)。自身对照组眼轴及屈光度均有增加,MMP-2mRNA表达较同龄正常对照组有轻度上调,组间差异极显著(P<0.01)。免疫组化显示,MMP-2表达的增高主要在巩膜成纤维细胞层。结论外源性视黄酸能够上调巩膜MMP-2的转录和表达,并可能通过这一途径促进眼轴及屈光度的增加。

AIM: To explore the influence of ectogenesis retinoic acid (RA) on the elongation and remodeling in chick eyes. · METHODS: Ninety 1-day-old white leghorn chicks were divided randomly and equally into 3 groups. In Experimental Group, RA retrobulbar injection was performed every other day in right eyes, and the left eyes served as Self-Control Group. In Negative Control Group, Saline retrobulbar injection was performed on right eyes. There was no treatment in Normal Control Group. Eyesight and axis oculi in both eyes were measured in 1/3 of each group at 4, 8 and 14d after the first injection. Both eyes were collected after the measurement. The total RNA in the posterior sclera was extracted traditionally, and expression levels of MMP-2 mRNA were analyzed by single step reverse transcription-polymerase chain reaction (RT-PCR). The protein level of MMP-2 was analyzed by immunohistochemistry as well.· RESULTS: According to the comparison between normal and negative controlled groups, RA injection made significantly elongation of axis oculi and development of eyesight, as well as a higher level of MMP-2 mRNA expression in the posterior sclera. There was statistical difference between normal and self-controlled groups (P < 0.01). Immunohistochemistry showed that the expression of MMP-2 was mainly changed in the fibroblast cell layer of sclera.· CONCLUSION: Retinoic acid can up-regulate the level of MMP-2 mRNA expression in the posterior sclera, and raise the elongation of axis oculi and development of eyesight as well. It may be an important factor in manipulating eye elongation.·