Culture of Retinal Neurons

2003 ◽  
pp. 15-26 ◽  
Keyword(s):  
Retinal Neurons

scholarly journals Photoelectric Dye, NK-5962, as a Potential Drug for Preventing Retinal Neurons from Apoptosis: Pharmacokinetic Studies Based on Review of the Evidence

Life ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 591
Author(s):  
Toshihiko Matsuo ◽  
Shihui Liu ◽  
Tetsuya Uchida ◽  
Satomi Onoue ◽  
Shinsaku Nakagawa ◽  
...  
Keyword(s):  
Biological Evaluation ◽  
Pharmacokinetic Studies ◽  
Retinal Neurons ◽  
Retinal Cells ◽  
Intravitreous Injection ◽  
Rcs Rats ◽  
Photoelectric Dye ◽  
Dark Conditions

NK-5962 is a key component of photoelectric dye-based retinal prosthesis (OUReP). In testing the safety and efficacy, NK-5962 was safe in all tests for the biological evaluation of medical devices (ISO 10993) and effective in preventing retinal cells from death even under dark conditions. The long-term implantation of the photoelectric dye-coupled polyethylene film in the subretinal space of hereditary retinal dystrophic (RCS) rats prevented neurons from apoptosis in the adjacent retinal tissue. The intravitreous injection of NK-5962 in the eyes of RCS rats, indeed, reduced the number of apoptotic cells in the retinal outer nuclear layer irrespective of light or dark conditions. In this study, we reviewed the in vitro and in vivo evidence of neuroprotective effect of NK-5962 and designed pharmacokinetic experiments. The in vitro IC50 of 1.7 μM, based on the protective effect on retinal cells in culture, could explain the in vivo EC50 of 3 μM that is calculated from concentrations of intravitreous injection to prevent retinal neurons from apoptosis. Pharmacokinetics of NK-5962 showed that intravenous administration, but not oral administration, led to the effective concentration in the eye of rats. NK-5962 would be a candidate drug for delaying the deterioration of retinal dystrophy, such as retinitis pigmentosa.

Electrical stimulation of retinal neurons in epiretinal and subretinal configuration using a multicapacitor array

2012 ◽  
Vol 107 (10) ◽  
pp. 2742-2755 ◽  
Author(s):  
Max Eickenscheidt ◽  
Martin Jenkner ◽  
Roland Thewes ◽  
Peter Fromherz ◽  
Günther Zeck
Keyword(s):  
Electrical Stimulation ◽  
Ganglion Cells ◽  
Ex Vivo ◽  
Biophysical Model ◽  
Retinal Neurons ◽  
Direct Stimulation ◽  
Tungsten Electrode ◽  
Partial Restoration ◽  
Low Amplitude ◽  
Stimulation Of

Electrical stimulation of retinal neurons offers the possibility of partial restoration of visual function. Challenges in neuroprosthetic applications are the long-term stability of the metal-based devices and the physiological activation of retinal circuitry. In this study, we demonstrate electrical stimulation of different classes of retinal neurons with a multicapacitor array. The array—insulated by an inert oxide—allows for safe stimulation with monophasic anodal or cathodal current pulses of low amplitude. Ex vivo rabbit retinas were interfaced in either epiretinal or subretinal configuration to the multicapacitor array. The evoked activity was recorded from ganglion cells that respond to light increments by an extracellular tungsten electrode. First, a monophasic epiretinal cathodal or a subretinal anodal current pulse evokes a complex burst of action potentials in ganglion cells. The first action potential occurs within 1 ms and is attributed to direct stimulation. Within the next milliseconds additional spikes are evoked through bipolar cell or photoreceptor depolarization, as confirmed by pharmacological blockers. Second, monophasic epiretinal anodal or subretinal cathodal currents elicit spikes in ganglion cells by hyperpolarization of photoreceptor terminals. These stimuli mimic the photoreceptor response to light increments. Third, the stimulation symmetry between current polarities (anodal/cathodal) and retina-array configuration (epi/sub) is confirmed in an experiment in which stimuli presented at different positions reveal the center-surround organization of the ganglion cell. A simple biophysical model that relies on voltage changes of cell terminals in the transretinal electric field above the stimulation capacitor explains our results. This study provides a comprehensive guide for efficient stimulation of different retinal neuronal classes with low-amplitude capacitive currents.

scholarly journals Decreased Expression of DREAM Promotes the Degeneration of Retinal Neurons

PLoS ONE ◽  
2015 ◽  
Vol 10 (5) ◽  
pp. e0127776 ◽  
Author(s):  
Shravan Chintala ◽  
Mei Cheng ◽  
Xiao Zhang
Keyword(s):  
Retinal Neurons

Adrenergic retinal neurons of some new world monkeys

1969 ◽  
Vol 100 (3) ◽  
pp. 364-375 ◽  
Author(s):  
B. Ehinger ◽  
B. Falck
Keyword(s):  
New World ◽  
New World Monkeys ◽  
Retinal Neurons

Mapping photoreceptor and postreceptoral labelling patterns using a channel permeable probe (agmatine) during development in the normal and RCS rat retina

2002 ◽  
Vol 19 (1) ◽  
pp. 61-70 ◽  
Author(s):  
MICHAEL KALLONIATIS ◽  
GUIDO TOMISICH ◽  
JOHN W. WELLARD ◽  
LISA E. FOSTER
Keyword(s):  
Amacrine Cells ◽  
Horizontal Cells ◽  
Retinal Neurons ◽  
Inner Retina ◽  
Strong Signal ◽  
Rcs Rat ◽  
Sequential Development ◽  
Nuclear Labelling ◽  
Multiple Samples ◽  
Neurochemical Development

The aim of this study was to determine whether agmatine, a channel permeable probe, can identify photoreceptor dysfunction in the Royal College of Surgeons (RCS) retina at an earlier stage to that shown by apoptosis or anatomical markers, and also characterize the neurochemical development of the inner retina in the normal and degenerating rat. We used isolated retinas at different ages incubated in physiological media containing agmatine. Subsequently, postembedding immunocytochemistry was used to determine the number of labelled photoreceptors and the labelling pattern within postreceptoral neurons. Agmatine labelling patterns revealed a sequential development of retinal neurons beginning at postnatal day (PND)11/12 with most horizontal cells, a few ganglion and amacrine cells, showing a strong signal. The neurochemical development progressed rapidly, and reflects to a large part the known distribution of glutamate receptors, with inner nuclear labelling being evident by PND14, continuing with the same pattern of labelling in adulthood for the control retina. The RCS retina showed markedly reduced agmatine labelling in the inner retina at PND20. A rapid increase in photoreceptor AGB labelling was evident during the degeneration phase. Multiple samples at PND14 and PND16 confirmed a significant increase of labelled photoreceptors in the RCS retina.

Fragmented DNA transport in dendrites of retinal neurons during apoptotic cell death

2004 ◽  
Vol 1007 (1-2) ◽  
pp. 183-187 ◽  
Author(s):  
Akira Hara ◽  
Masayuki Niwa ◽  
Masako Kumada ◽  
Nami Kitaori ◽  
Tetsuya Yamamoto ◽  
...  
Keyword(s):  
Cell Death ◽  
Apoptotic Cell ◽  
Apoptotic Cell Death ◽  
Retinal Neurons ◽  
Dna Transport ◽  
Fragmented Dna
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