Open AccessStimulus-evoked outer segment changes occur before the hyperpolarization of retinal photoreceptors
Author(s) -
Yiming Lu,
Benquan Wang,
David R. Pepperberg,
Xincheng Yao
Publication year - 2016
Publication title -
biomedical optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.362
H-Index - 86
ISSN - 2156-7085
DOI - 10.1364/boe.8.000038
Subject(s) - retinal , visual phototransduction , hyperpolarization (physics) , retina , electrophysiology , neuroscience , depolarization , stimulus (psychology) , biology , optical coherence tomography , biophysics , chemistry , optics , physics , psychology , biochemistry , organic chemistry , nuclear magnetic resonance spectroscopy , psychotherapist
Transient retinal phototropism (TRP) has been predominantly observed in rod photoreceptors activated by oblique visible light stimulation. Dynamic confocal microscopy and optical coherence tomography (OCT) have revealed rod outer segment (ROS) movement as the physical source of TRP. However, the physiological source of ROS movement is still not well understood. In this study, concurrent near-infrared imaging of TRP and electroretinogram (ERG) measurement of retinal electrophysiology revealed that ROS movement occurs before the onset of the ERG a-wave, which is known to reflect the hyperpolarization of retinal photoreceptors. Moreover, substitution of normal superfusing medium with low-sodium medium reversibly blocked the photoreceptor ERG a-wave, but largely preserved the stimulus-evoked ROS movements. Our experimental results and theoretical analysis indicate that early, disc-based stages of the phototransduction cascade, which occur before the hyperpolarization of retinal photoreceptors, contribute to the TRP associated ROS movement.