Purpose:To investigate the rhodopsin expression in form-deprived and defocus myopiain guinea pig and study the relationship between the rhodopsin expression andexperimental myopia.
Methods:Fourty guinea pigs were randomized into the form-deprived group and thedefocus group (n= 20 ). Guinea pigs in the form-deprived group wore a diffuser(rigidgass-permeable contact lens(RGP)on one eye since one week after birth. Those in defocus group wore a -4 D RGPon one eye. The contralateral eyes were left ascontrol. Refraction, axial length and depth of vitreous cavity were measured after 1and 2 weeks respectively. Retina were dissected at 10 ~ 12 o'clock in the moring.The level of rhodopsin and its mRNA were observed through Western-blot and real-time PCR respectively.
Result:There is no difference between form-deprived group, defocus group and controlgroups(except refraction in form-deprived group). One week later, there is nodifference between the form-deprived group, the defocus group and the control groups(except refraction in form-deprived group). Two weeks later, eyes in the form-deprivedgroup and the defocus group became myopic. Its axial length lengthened and depth ofvitreous cavity appeared deep. The form-deprived groups showed an increasedexpression of rhodopsin and its mRNA compared to the control groups. There is nodifference between the defocus group and the control groups.
Conclusion : Expression of rhodopsin might involve formation of form-deprived myopia,but has less influence on defocus myopia.