Barathi V A, Beuerman Roger W
Singapore Eye Research Institute, Singapore.
Mol Vis. 2011 Mar 9;17:680-92.
To investigate the effect of atropine on the development of spectacle lens induced myopia in the mouse and to determine if the level of mRNAs for the muscarinic receptor subtypes (M(1) - M(5)) is affected by atropine treatment.
Experimental myopia was developed in Balb/CJ (BJ) mice by placing -10 diopter spectacle lens on post-natal day 10 over the right eyes of 150 mice (n=10 in each group, 5 repetitions) for six weeks. After 2 weeks of lens wearing, the atropine group received a daily sub-conjunctival injection (10 µl) of 1% atropine sulfate and the saline group received daily 10 µl of 0.9% normal saline for 4 weeks. In addition, myopia was developed in C57BL/6 (B6) mice by placing -10 D spectacle lens on post-natal day 10 over the right eyes of 60 mice (n=10 in each group, 2 repetitions) for six weeks with and without atropine treatment. Refraction and axial length was measured at 2, 4, and 6 weeks after treatments. RT-PCR and northern blots were performed using specific primers for M(1)-M(5), and products sequenced. Real-time PCR was used to quantify message levels.
Axial length of myopic eyes was 111% of their controls without atropine treatment and 103% of controls after atropine (p<0.01). Refraction shifted from myopic to emmetropic after atropine was administered in both pigmented and non-pigmented eyes. Corneal thickness, anterior chamber depth, corneal curvature and retinal thickness were not significantly different with and without atropine treatment (p=0.14). The lens thickness and vitreous chamber depth were significantly reduced after receiving atropine (p<0.05). Real-time PCR showed that message levels for M(1), M(3), and M(4) were upregulated in myopic sclera after atropine treatment, but M(2) and M(5) showed little change.
The present study shows that 1% atropine reduces myopia progression in both pigmented and non-pigmented mice eyes. Axial length and vitreous chamber depth appear to be the main morphological parameters related to myopia. The results suggest that atropine may act on one or more muscarinic receptors to differentially regulate expression levels of specific receptors.
研究阿托品对小鼠框架眼镜诱导性近视发展的影响，并确定毒蕈碱受体亚型（M(1)-M(5)）的mRNA水平是否受阿托品治疗的影响。
在出生后第10天，给150只Balb/CJ（BJ）小鼠（每组10只，重复5次）的右眼佩戴-10屈光度的框架眼镜，持续6周，以诱导实验性近视。戴镜2周后，阿托品组每天结膜下注射（10μl）1%硫酸阿托品，生理盐水组每天注射10μl 0.9%生理盐水，持续4周。此外，给60只C57BL/6（B6）小鼠（每组10只，重复2次）在出生后第10天的右眼佩戴-10 D框架眼镜，持续6周，分为有阿托品治疗组和无阿托品治疗组。在治疗后2、4和6周测量屈光和眼轴长度。使用针对M(1)-M(5)的特异性引物进行RT-PCR和Northern印迹分析，并对产物进行测序。使用实时PCR定量mRNA水平。
未用阿托品治疗的近视眼中眼轴长度是其对照的111%，用阿托品治疗后为对照的103%（p<0.01）。在有色素和无色素眼中，给予阿托品后屈光从近视转变为正视。阿托品治疗组和未治疗组的角膜厚度、前房深度、角膜曲率和视网膜厚度无显著差异（p=0.14）。接受阿托品治疗后晶状体厚度和玻璃体腔深度显著降低（p<0.05）。实时PCR显示，阿托品治疗后近视巩膜中M(1)、M(3)和M(4)的mRNA水平上调，但M(2)和M(5)变化不大。
本研究表明，1%阿托品可降低有色素和无色素小鼠眼中的近视进展。眼轴长度和玻璃体腔深度似乎是与近视相关的主要形态学参数。结果表明，阿托品可能作用于一种或多种毒蕈碱受体，以差异调节特定受体的表达水平。
