Purchase this article with an account.
Tatiana V. Tkatchenko, Andrei V. Tkatchenko; Photopic Visual Input Promotes Emmetropization in Mice. Invest. Ophthalmol. Vis. Sci. 2011;52(14):6290.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Mice are nocturnal animals and it is widely believed that they have poor vision because of their small eyes, low visual acuity, and adaptation to dim-light habitat. However, mice see very well under photopic conditions, and we have recently demonstrated that mice develop higher degrees of both form-deprivation and lens-induced myopia if placed in photopic conditions (constant light). It was not clear though how constant light effects normal refractive eye development in mice. The purpose of this study was to investigate how constant light affects refractive eye development in mice.
Using a high-resolution automated eccentric infrared photorefractor, the normal refractive eye development was compared under regular (12 h light/12 h dark) light regiment and under constant light (200 lux) conditions in P21-P89 C57BL/6J mice.
The average refractive errors in the regular-light-regiment group were -13.2 ± 2.0 D at P21, -0.5 ± 1.5 D at P32, +0.3 ± 0.9 D at P40, +1.2 ± 1.7 D at P67 and +3.6 ± 2.3 D at P89. The average refractive errors in the constant-light-regiment group were -12.5 ± 1.2 D at P21, -1.0 ± 0.9 D at P32, +0.1 ± 0.9 D at P40, +0.4 ± 1.0 D at P67 and 0.0 ± 0.5 D at P89. Although we did not find statistically significant differences between two experimental groups at any of the ages analyzed, except for P89 (P21, P = 0.2427; P32, P = 0.3352; P40, P = 0.6012; P67, P = 0.0770; P89, P < 0.0001), our data suggest that mice, which were raised in the constant light conditions (hence photopic conditions), maintain emmetropic refractive status longer than animals raised under the regular light regiment. Animals in the regular-light-regiment group exhibited hyperopic refractive shift, which began at P67 and increased at P89, whereas mice in the constant-light-regiment group remained emmetropic at these ages.
Constant light do not have any detrimental effect on refractive development in young mice. Photopic visual input appears to promote emmetropization in mice.
This PDF is available to Subscribers Only