Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, Irvine, United States.
John A. Moran Eye Center, Department of Ophthalmology and Visual Sciences, University of Utah, Salt Lake City, United States.
Elife. 2020 Sep 22;9:e59422. doi: 10.7554/eLife.59422.
Neuronal plasticity of the inner retina has been observed in response to photoreceptor degeneration. Typically, this phenomenon has been considered maladaptive and may preclude vision restoration in the blind. However, several recent studies utilizing triggered photoreceptor ablation have shown adaptive responses in bipolar cells expected to support normal vision. Whether such homeostatic plasticity occurs during progressive photoreceptor degenerative disease to help maintain normal visual behavior is unknown. We addressed this issue in an established mouse model of Retinitis Pigmentosa caused by the P23H mutation in rhodopsin. We show robust modulation of the retinal transcriptomic network, reminiscent of the neurodevelopmental state, and potentiation of rod - rod bipolar cell signaling following rod photoreceptor degeneration. Additionally, we found highly sensitive night vision in P23H mice even when more than half of the rod photoreceptors were lost. These results suggest retinal adaptation leading to persistent visual function during photoreceptor degenerative disease.
内视网膜的神经元可塑性已被观察到对光感受器变性的反应。通常,这种现象被认为是适应不良的,可能会阻止盲人的视力恢复。然而,最近的几项利用触发光感受器消融的研究表明,双极细胞会出现适应性反应,这有望支持正常视力。在进行性光感受器退行性疾病中,这种同源性可塑性是否会发生以帮助维持正常的视觉行为尚不清楚。我们在由视紫红质 P23H 突变引起的色素性视网膜炎的既定小鼠模型中解决了这个问题。我们发现视网膜转录组网络的强大调节,类似于神经发育状态,以及 rod-rod 双极细胞信号的增强,在 rod 光感受器变性之后。此外,我们发现 P23H 小鼠即使在失去一半以上的 rod 光感受器后,仍具有高度敏感的夜视能力。这些结果表明,在光感受器退行性疾病期间,视网膜适应导致持续的视觉功能。