Experimental Sciences
c-Fos expression in visual cortex of infant rhesus monkeys with myopia induced by hyperopic defocus
Junshu Wu, Xiangyin Sha, Hua Zheng, Yinghui Liu, Jian Ge
Published 2018-11-10
Cite as Chin J Exp Ophthalmol, 2018, 36(11): 847-851. DOI: 10.3760/cma.j.issn.2095-0160.2018.11.006
Abstract
ObjectiveTo observe c-Fos expression in visual cortex of infant rhesus monkeys with myopia induced by hyperopic defocus and preliminarily investigate the possibility of visual cortex participating in myopia.
MethodsEight SPF grade healthy infant rhesus monkeys aged 20 to 30 days were randomly divided into hyperopic defocused group and control group, 4 monkeys for each group.The monkeys in hyperopic defocused group wore -3 D spectacle lenses.The monkeys in control group wore 0 D lenses.The monkeys' refractive error, corneal topography, vitreous chamber depth were measured at the start of lens wear and at 2, 4, 6, 8, 12 weeks post-treatment.At 12 weeks post-treatment, the visual cortex tissues were removed for c-Fos protein measurement by immunohistochemistry and Western blot assays.The results were analyzed semiquantitatively to compare the differences of c-Fos expression between hyperopic defocused group and control group.The use and care of the animals complied with Regulations for the Administration of Affair Concerning Experimental Animals by State Science and Technology Commission.This study protocol was approved by Ethic Committee of Zhongshan Ophthalmic Center (No.2013-014).
ResultsAfter 12 weeks' lens wear, the vitreous chamber elongation amplitude of hyperopic defocused group monkeys was more obvious than that of the control group ([0.93±0.24]mm vs.[0.72±0.09]mm; t=2.292, P=0.047). The decrease of hyperopic degrees of hyperopic defocused group monkeys was more obvious than that of the control group ([-3.23±1.36]D vs.[-1.55±0.52]D; t=-3.273, P=0.006). The eyes of hyperopic defocused group monkeys appeared a remarkable myopic shift after treatment.The number of c-Fos immunoreactive neurons was less in the hyperopic defocused group than that in the control group, with a statistically significant difference between them ([1 843±191]/mm2 vs.[2 296±503]/mm2; t=2.381, P=0.041). Western blot assay showed that the optical density of c-Fos protein in the hyperopic defocused group was significantly less than that in the control group (0.50±0.17 vs.0.99±0.22; t=-4.982, P<0.01).
ConclusionsHyperopic defocus, as an abnormal visual stimulus, can induce the onset of myopia in infant rhesus monkeys and inhibit c-Fos expression in visual cortex.Visual cortex may participate in myopia induced by hyperopic defocus.
Key words:
c-Fos; Myopia; Visual cortex; Rhesus monkey; Optical defocus
Contributor Information
Junshu Wu
Department of Ophthalmology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, China
Xiangyin Sha
Department of Ophthalmology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, China
Hua Zheng
State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
Yinghui Liu
State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
Jian Ge
State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
