Suematsu Naofumi, Sato Akinori Y, Kimura Akihiro, Shimegi Satoshi, Soma Shogo
Graduate School of Medicine, Osaka University, Osaka, Japan.
Department of Molecular Cell Physiology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Invest Ophthalmol Vis Sci. 2025 Mar 3;66(3):31. doi: 10.1167/iovs.66.3.31.
Retinitis pigmentosa (RP) is a leading cause of blindness and genetically induces impairment of the retinal epithelium and photoreceptors. In this study, we investigated the decline in the visual response and visual ability during disease progression. This understanding is crucial for disease staging in patients, establishing therapeutic plans in advance, and evaluating the effects of interventional treatments.
We used a rat model of inherited RP (Royal College of Surgeons [RCS] rats) and evaluated form visual acuity and light perception using behavioral tests and electrophysiological recordings in the dorsal lateral geniculate nucleus, superior colliculus, and primary visual cortex.
The perceptual form vision (detection of grating stimulus) was attenuated by 9 weeks old. The neural responses in the three early visual areas to flashing grating stimuli with various contrasts and spatial frequencies showed similar degeneration progress as the behavioral evaluations. Light perception (detection of a bright uniform light source) was maintained until at least 11 weeks old. The neural responses to the uniform flashlight stimulus in the three early visual areas were maintained during the same period.
Our findings suggest that form vision is primarily affected by the progression of RP, whereas non-form vision is potentially robust to retinal degeneration. This maintenance of light perception is likely due to the preserved function of intrinsically photosensitive retinal ganglion cells. These results provide useful and fundamental knowledge for evaluating the protective or restorative effects of experimental treatments for RP.
视网膜色素变性（RP）是导致失明的主要原因，会遗传导致视网膜上皮和光感受器受损。在本研究中，我们调查了疾病进展过程中视觉反应和视觉能力的下降情况。这种认识对于患者的疾病分期、提前制定治疗方案以及评估介入治疗的效果至关重要。
我们使用遗传性RP大鼠模型（皇家外科学院[RCS]大鼠），并通过行为测试以及在背外侧膝状体、上丘和初级视觉皮层进行电生理记录，来评估形觉视力和光觉。
9周龄时，感知性形觉视觉（光栅刺激检测）减弱。三个早期视觉区域对具有不同对比度和空间频率的闪烁光栅刺激的神经反应，与行为评估显示出相似的退化进程。光觉（明亮均匀光源检测）至少维持到11周龄。在此期间，三个早期视觉区域对均匀手电筒刺激的神经反应得以维持。
我们的研究结果表明，形觉视觉主要受RP进展的影响，而非形觉视觉对视网膜变性可能具有较强的抵抗力。光觉的这种维持可能归因于内在光敏视网膜神经节细胞的保留功能。这些结果为评估RP实验性治疗的保护或恢复效果提供了有用的基础知识。
