Objective To study the effects of different concentrations of atropine eye drops on guinea pigs with form-deprivation myopia; to analyze the potential mechanisms of atropine. Methods In this experimental study, 80 3-week-old guinea pigs weighing approximately 100 g were randomly assigned to 5 groups: 4 weeks of monocular form deprivation (n=8), 4 weeks of form deprivation and atropine (n=8 for each concentration subgroup), 4 weeks of form deprivation and 2 weeks of atropine (n=8 for each concentration subgroup), 4 weeks of atropine (n=6 for each concentration subgroup), and a control group(n=6). Pure atropine powder was dissolved in distilled water to create three different concentrations of atropine solution: 0.2%, 1.0%, 3.0%. The atropine eye drops were applied once every morning at 8∶30-9∶00. All the groups underwent biometric measurements (refraction, corneal curvature, axial length, etc.) at three timepoints: prior to the experiment, 2 weeks into the experiment, and at the end of the experiment. Immunofluorescence was used to mark the guinea pig retinal cells that had a positive expression of glucagon. The results were analyzed with a paired-sample t test and two-way repeated measures ANOVA. Results After 2 weeks of form deprivation in the monocular form-deprived group, the experimental eyes developed myopia with a deepening of the vitreous chamber and an elongation of the ocular axis compared to the contralateral eyes. The difference was statistically significant (t=-11.09, 7.89, 3.73, P<0.05). Four weeks later, the experimental eyes had an even greater myopic shift. In the group with 4 weeks of form deprivation and atropine, there were no significant differences after 2 weeks when changes in refraction, vitreous chamber depth and axial length were compared between the experimental eyes and contralateral eyes of all three subgroups. Furthermore, there were no statistically significant differences between the contralateral and experimental eyes in each subgroup compared to the monocular form-deprived group (F=26.335, 6.479, 6.910, P<0.05). After 4 weeks, in the group with 4 weeks of form deprivation and atropine, the experimental eyes in all three subgroups began to develop myopia compared to the contralateral eyes (t=-4.67, -7.54, -2.78, P<0.05). Meanwhile, the vitreous chamber was deepening and the axis was elongating, but there were still statistically significant differences between the contralateral and experimental eyes of each subgroup compared to the monocular form-deprivation group (F=16.962, 5.193, 6.882, P<0.05). However, there were no significant differences for any refractive parameter among all three subgroups. There was no statistically significant difference for any refractive parameter when the experimental/contralteral eyes of each subgroup in the group with 2 weeks of form deprivation plus 2 weeks of atropine were compared to the group with 4 weeks of form deprivation. None of the guinea pig retinal cells in any group were marked to have a positive expression of glucagon. Conclusion The 3% concentration atropine eye drops can partly inhibit form-deprivation myopia by preventing the deepening of the vitreous chamber and elongation of the ocular axis in guinea pigs, and the effect of atropine does not show a concentration-dependent pattern. The use of atropine during the latter stage of form deprivation cannot limit the progress of myopia. Glucagon is not involved in the effect of atropine on the development of form-deprivation myopia in guinea pigs.
叶凌颖,张森,潘妙珍,周翔天,蒋丽琴. 不同浓度阿托品滴眼液对豚鼠形觉剥夺性近视的影响[J]. 中华眼视光学与视觉科学杂志, 2015, 17(12): 730-735.
Ye Lingying,Zhang Sen,Pan Miaozhen,Zhou Xiangtian,Jiang Liqin. Effects of different concentrations of atropine eye drops on guinea pigs with form-deprivation myopia. Chinese Journal of Optometry Ophthalmology and Visual science, 2015, 17(12): 730-735. DOI: 10.3760/cma.j.issn.1674-845X.2015.12.007
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