Shuo Yang1,2, Heng He1, Ying Zhu1, Xing Wan1, Long-Fang Zhou1, Juan Wang2, Wen-Feng Wang1, Lei Liu2, Bin Li1. 1. Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China. 2. Department of Optometry and Ophthalmology Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China.
Abstract
BACKGROUND: To examine interactions between optic nerves. METHODS: A total of 24 Sprague-Dawley rats received unilateral intravitreal injections. The rats were equally divided into four groups: group A was administered an adeno-associated virus (AAV) carrying an exogenous gene (ND4; rAAV-ND4); group B, AAV carrying a green fluorescent protein (GFP; rAAV-GFP); group C, fluorogold (FG) nerve tracer dye; and group D, phosphate-buffered saline (PBS) as a control. Two weeks later, GFP expression was evaluated in both retinas and optic nerves of group B rats after frozen sectioning. The presence of FG was also evaluated in group C optic nerves by fluorescent microscopy after frozen sectioning. Four weeks after injection, ND4 expression was evaluated in both eyes of groups A and D using western blotting and immunofluorescence. RESULTS: FG was observed in the optic chiasm posterior segment along the optic nerve of injected eyes. Some FG reached the anterior optic nerve of the non-injected eye. GFP fluorescence was observed only in the retina of the injected eye but not in the contralateral retina or either optic nerve. ND4 expression was significantly different between injected and non-injected eyes but not between the non-injected eyes in groups A and D. CONCLUSION: Unilaterally injected material can reach the contralateral optic nerve through axoplasmic transport. It is possible that this the only mechanism by which the optic nerves directly communicate.
BACKGROUND: To examine interactions between optic nerves. METHODS: A total of 24 Sprague-Dawley rats received unilateral intravitreal injections. The rats were equally divided into four groups: group A was administered an adeno-associated virus (AAV) carrying an exogenous gene (ND4; rAAV-ND4); group B, AAV carrying a green fluorescent protein (GFP; rAAV-GFP); group C, fluorogold (FG) nerve tracer dye; and group D, phosphate-buffered saline (PBS) as a control. Two weeks later, GFP expression was evaluated in both retinas and optic nerves of group B rats after frozen sectioning. The presence of FG was also evaluated in group C optic nerves by fluorescent microscopy after frozen sectioning. Four weeks after injection, ND4 expression was evaluated in both eyes of groups A and D using western blotting and immunofluorescence. RESULTS: FG was observed in the optic chiasm posterior segment along the optic nerve of injected eyes. Some FG reached the anterior optic nerve of the non-injected eye. GFP fluorescence was observed only in the retina of the injected eye but not in the contralateral retina or either optic nerve. ND4 expression was significantly different between injected and non-injected eyes but not between the non-injected eyes in groups A and D. CONCLUSION: Unilaterally injected material can reach the contralateral optic nerve through axoplasmic transport. It is possible that this the only mechanism by which the optic nerves directly communicate.