Stone R A, Lin T, Iuvone P M, Laties A M
Department of Ophthalmology, University of Pennsylvania School of Medicine, Scheie Eye Institute, Philadelphia 19104-6075.
Ciba Found Symp. 1990;155:45-57; discussion 57-62. doi: 10.1002/9780470514023.ch4.
A vision-dependent feedback mechanism contributes to the regulation of postnatal eye growth and refraction; this mechanism is located at least in part in the retina. In chicks and rhesus monkeys, visual deprivation leads to ocular enlargement and a myopic refractive error, and it also reduces the retinal concentration of dopamine. In neonatal chicks, local application of the dopamine agonist apomorphine limits the excessive axial elongation that is associated with visual deprivation. Both D1 and D2 dopamine receptor mechanisms may participate. Remarkably, apomorphine is geometrically selective, not limiting the exaggerated equatorial growth that occurs during visual deprivation. Preliminary results in neonatal rhesus monkeys indicate that apomorphine eye drops also suppress exaggerated axial growth and myopic refractive error during visual deprivation; equatorial diameters were not measured. Our observations are consistent with a retinal hypothesis for emmetropization and suggest that retinal dopamine participates in a mechanism linking ocular growth control to vision. In addition, we conclude that axial and equatorial dimensions are independently regulated in the chick.
一种依赖视觉的反馈机制有助于调节出生后眼睛的生长和屈光；这种机制至少部分位于视网膜中。在小鸡和恒河猴中，视觉剥夺会导致眼球增大和近视性屈光不正，同时还会降低视网膜中多巴胺的浓度。在新生小鸡中，局部应用多巴胺激动剂阿扑吗啡可限制与视觉剥夺相关的过度眼轴伸长。D1和D2多巴胺受体机制可能都参与其中。值得注意的是，阿扑吗啡具有几何选择性，不会限制视觉剥夺期间发生的赤道部过度生长。新生恒河猴的初步结果表明，阿扑吗啡滴眼液也可抑制视觉剥夺期间的过度眼轴生长和近视性屈光不正；未测量赤道直径。我们的观察结果与正视化的视网膜假说一致，并表明视网膜多巴胺参与了一种将眼生长控制与视觉联系起来的机制。此外，我们得出结论，小鸡的眼轴和赤道维度是独立调节的。
