Epiretinal electrical stimulation and the inner limiting membrane in rat retina.
In this paper we aim to quantify the effect of the inner limiting membrane (ILM) of the retina on the thresholds for epiretinal electrical stimulation of retinal ganglion cells by a microelectronic retinal prosthesis. A pair of bipolar stimulating electrodes was placed either above (on the epiretinal surface) or below the ILM while we made whole-cell patch-clamp recordings from retinal ganglion cells in an isolated rat retinal whole-mount preparation. Across our cell population we found no significant difference in the median threshold stimulus amplitudes when the stimulating electrodes were placed below as opposed to above the ILM (p = 0.08). However, threshold stimulus amplitudes did tend to be lower when the stimulating electrodes were placed below the ILM (30 µA vs 56 µA).
National Vision Research Institute, Australian College of Optometry, Carlton, VIC 3053, Australia.
Shaun L
SL
Cloherty
Raymond C S
RC
Wong
Alex E
AE
Hadjinicolaou
Hamish
H
Meffin
Michael R
MR
Ibbotson
Brendan J
BJ
O'Brien
D000818:Animals; D004558:Electric Stimulation; D005074:Evoked Potentials, Visual / Q000502:physiology; D008839:Microelectrodes; D018408:Patch-Clamp Techniques; D051381:Rats; D012160:Retina / Q000502:physiology*; D012165:Retinal Ganglion Cells / Q000502:physiology