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Published on: June 2, 2022
Stimulus-evoked outer segment changes in rod photoreceptors
Xiaohui Zhao1, Damber Thapa2, Benquan Wang2
1Hebei University, College of Physics Science and Technology, Hebei Key Lab of Optic-Electronic Information Materials, Baoding 071002, ChinabUniversity of Illinois at Chicago, Department of Bioengineering, Chicago, Illinois 60607, United States.
Abstract:
Rod-dominated transient retinal phototropism (TRP) has been recently observed in freshly isolated mouse and frog retinas. Comparative confocal microscopy and optical coherence tomography revealed that the TRP was predominantly elicited from the rod outer segment (OS). However, the biophysical mechanism of rod OS dynamics is still unknown. Mouse and frog retinal slices, which displayed a cross-section of retinal photoreceptors and other functional layers, were used to test the effect of light stimulation on rod OSs. Time-lapse microscopy revealed stimulus-evoked conformational changes of rod OSs. In the center of the stimulated region, the length of the rod OS shrunk, while in the peripheral region, the rod OS swung toward the center region. Our experimental observation and theoretical analysis suggest that the TRP may reflect unbalanced rod disc-shape changes due to localized visible light stimulation.
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