摘要目的 研究形觉剥夺和光学离焦性豚鼠近视眼视蛋白的表达变化,探讨视蛋白表达与实验性近视眼之间的关系.方法 实验研究.50只豚鼠随机分为形觉剥夺组、光学离焦组(每组20只)和正常对照组(10只),形觉剥夺组豚鼠出生1周后单眼戴半透明(半透明薄膜贴于平镜表面)硬性角膜接触镜(RGPCL),光学离焦组豚鼠出生1周后单眼戴-4.00 D的RGPCL,另一眼为对照眼.1、2周后各组分别测量屈光度数、眼轴长度和玻璃体腔深度,并于上午10 ～ 12点钟取材,实时荧光定量PCR观察视蛋白mRNA的变化,免疫印迹法检测视蛋白的变化.近视眼动物模型建立的数据采用两因素方差分析联合q检验,PCR和免疫印迹检测结果行配对t检验.结果 造模2周后,形觉剥夺组和光学离焦组屈光度数分别为(-4.00 ±0.87)和(-2.00±1.17)D,相对于对侧眼及对照组差异有统计学意义(F=203.98,88.66；P＜0.05),同时伴有玻璃体腔深度(F=258.26,46.67)及眼轴(F=94.19,11.72)的延长,和对侧眼及正常对照组相比,差异有统计学意义(P＜0.05).短波长敏感视蛋白(S-opsin)mRNA在形觉剥夺和光学离焦组中表达均增加,S-opsin mRNA的内参校正值在造模2周时分别为0.752±0.05和1.117 ±0.13,较对照眼0.536 ±0.04和0.772±0.10差异有统计学意义(t=6.10,6.28;P ＜0.05).长波长敏感视蛋白(L-opsin)在形觉剥夺及光学离焦2周时mRNA的内参校正值均为0.42 ±0.01,较对照眼的0.24±0.01和0.34±0.04表达均增加(t=6.30,4.93；P＜0.05).免疫印迹检查结果亦提示S-opsin和L-opsin在形觉剥夺和光学离焦组中表达较对照眼增加.结论 视锥细胞可能是视网膜感受形觉剥夺和光学离焦信息的部位,视蛋白表达变化可能启动实验性豚鼠近视眼的形成.

abstractsObjective To investigate the opsin expression in form-deprived and defocus myopia in guinea pig and to study the relationship between the opsin expression and the experimental myopia.Methods Fifty guinea pigs were randomized into form-deprived group,defocus group ( n =20 in each group) and normal group (n =10).Guinea pigs in form-deprived group wore a diffuser RGP on one eye since one week after birth.Those in defocus group wore - 4.00 D RGP on one eye.The contralateral eyes wore 0 D RGP were used as the control.Refraction,axial length and depth of vitreous cavity were measured after 1 and 2 weeks.Animals were sacrificed and the retina were dissected at 10:00-12:00 AM.The level of opsin and its mRNA were measured by Western-blot and real-time PCR,respectively. Results Two weeks after the experiment,the refraction in form-deprived group and defocus group were ( - 4.00 ± 0.87 ) and ( - 2.00 ± 1.17) D respectively,which were significant different compared with contralateral eyes or normal control group ( F =203.98,88.66,P ＜ 0.05 ).These also accompany with increase of axial length and depth of vitreous cavity in form-deprived group and defocus group.Expression of S-opsin mRNA were increased both in form-deprived and defocus groups and the ratios of S-opsin mRNA/β-actin expression were 0.752 ±0.05and 1.117 ± 0.13 in two weeks treatment,which were significant different from contralateral eyes( the ratios of S-opsin mRNA/β-actin expression were 0.536 ± 0.04 and 0.772 ± 0.10.t =6.10,6.28,P ＜ 0.05 ).Similar findings were also demonstrated in the expression of L-opsin mRNA,which were increased in formdeprived group and defocus group ( the ratios of L-opsin mRNA/β-actin expression were 0.42 ± 0.01 )compared with contralateral eyes ( the ratios were 0.24 ± 0.0 and 0.34 ± 0.04.t =6.30,4.93,P ＜ 0.05 )after two weeks experiment.The western-blot results also indicated the high expression of S-opsin and L-opsin level compared to contralateral eyes in form-deprived and defocus groups.Conclusions Cone might be the detector receiving the signal of form-deprivation and defocus.Changes of opsin expression might play a role in the occurrence of experimental myopia in guinea pig.