豚鼠形觉剥夺性近视视网膜早基因c-fos的动态表达

Changes of c-fos expression induced by form deprivation myopia in guinea pigs

目的建立豚鼠形觉剥夺性近视(form-deprivationmyopia,FDM)动物模型,并对豚鼠形觉剥夺性近视形成及恢复过程中视网膜早基因c-fos的动态变化进行观察,研究豚鼠FDM中视网膜信号转导及抑制近视的可能分子机制。方法3周三色豚鼠40只,随机均分为4组:遮盖前组、单眼遮盖1周组、单眼遮盖2周组及去遮盖组。对各组进行视网膜检影和A超测眼轴,分别运用免疫组化和RT-PCR观察各组视网膜c-fos蛋白及mRNA的表达和变化。结果遮盖2周后,遮盖眼较对照眼呈高度相对近视(-8.8 D),视网膜c-fos表达明显下调,双眼屈光度、眼轴和视网膜c-fos的表达差异均有显著性(P<0.05);遮盖2周后,去遮盖1周,去遮盖眼较对照眼呈中度相对近视(-5.9 D),但去遮盖前后屈光度及眼轴差异无显著性(P>0.05),去遮盖眼较对照眼视网膜c-fos的表达明显上调,差异有非常显著性(P<0.01)。结论形觉剥夺能成功诱导豚鼠近视的发生及发展,并抑制视网膜c-fos的表达,而去除形觉剥夺可抑制近视的发展,并诱导视网膜c-fos的表达上调,证明c-fos的表达规律不仅反映外界视觉环境对眼的刺激,并与近视发展规律呈负相关,可能参与视网膜的信号转导和近视的抑制机制。

Objective To investigate expression of immediate-early gene c-fos in retina and factors involved in regulation of ocular growth in eyes treated by form deprivation.Methods Forty guinea pigs of three weeks old were randomly assigned to four groups： group 1 underwent monocular form deprivation （MFD） by a opaque headgear for 1 week; group 2 was treated with similar deprivation for 2 weeks; group 3 recoved for 1 week from 2-week deprivation and group 4 free of form deprivafon as a normal control. Development in both refraction and axial length of the eye was measured before and the experimental period. Expression of immediate-early gene c-fos was quantifled by immunobistochemistry and RT-PCR. Results The MFD eyes showed significant myopia compared to the contralateral eyes and controlled groups with an increasing axial length and a down-redo dated expression of immediate-early gene c-fos （P 〈 0.05）. The recovered group had the refractive back to moderate myopia. And the expression of iramediate-early gene c-fos increased significantly in recoved group （ P 〈 0.01 ）. Conclusion Form deprivation myopia can be induced in guinea pigs. The level of expression in early gene c-fos was significantly oorrelated with the myopic development. Immediate-early gene c-fos may be a potential factor in the control of eye growth and play an important role in the signal transduction of retina.