Language
English
Publication Date
4-1-2023
Journal
Vision Research
DOI
10.1016/j.visres.2023.108187
PMID
36758452
PMCID
PMC11349081
PubMedCentral® Posted Date
8-27-2024
PubMedCentral® Full Text Version
Author MSS
Abstract
By analyzing light-evoked spike responses, cation currents (ΔIC) and chloride currents (ΔICl) of over 100 morphologically-identified retinal ganglion cells (GCs) in dark-adapted mouse retina, we found there are at least 14 functionally- and morphologically-distinct types of RGCs. These cells can be divided into 5 groups based on their patterns of spike response to whole field light steps (SRWFLS), a GC identification scheme commonly used in studies with extracellular recording techniques. We also found that all GCs in the mouse retina express strychnine-sensitive glycine receptors, and receive light-elicited chloride current (ΔICl) accompanied by a conductance increase from narrow-field, glycinergic amacrine cells. As the dark membrane potential of RGC are near the chloride-equilibrium potential, mouse GCs’ spike responses are mediated primarily by bipolar cells inputs, and modulated by “shunting inhibition” from narrow-field amacrine cells. Analysis of strychnine actions on light-evoked cation current ΔIC (bipolar cell inputs) in GCs suggests that narrow-field amacrine cells modulate GCs by sending ON-OFF crossover feedback signals to presynaptic bipolar cell axon terminals via sign-inverting glycinergic synapses, and the feedback signals are synergistic to the bipolar cell light responses. Therefore narrow-field amacrine cells enhance light-evoked bipolar cell inputs to GCs by presynaptic “synergistic addition”, besides the abovementioned postsynaptic “shunting inhibition” in GCs.
Keywords
Animals, Mice, Retinal Ganglion Cells, Amacrine Cells, Retina, Strychnine, Chlorides, Cations, Sustained and transient ganglion cells, ON, OFF and ON-OFF ganglion cells, glycineregic amacrine cells, narrow-field amacrine cells, light-evoked cation and chloride currents, light-evoked spike responses, feedforward synapse, feedback synapse, strychnine
Published Open-Access
yes
Recommended Citation
Ji-Jie Pang, Fan Gao, and Samuel M Wu, "Light Responses and Amacrine Cell Modulation of Morphologically-Identified Retinal Ganglion Cells in the Mouse Retina" (2023). Faculty and Staff Publications. 2774.
https://digitalcommons.library.tmc.edu/baylor_docs/2774