Involvement of glycinergic neurons in the diminished surround activity of ganglion cells in the dark-adapted rabbit retina

AbstractPrevious studies have reported that the surround responses of retinal ganglion cells weaken or disappear upon dark adaptation. The mechanism(s) by which this occurs is largely unknown, although changes in activity of retinal dopaminergic neurons have been implicated. In the light-adapted rabbit retina, the surround ON responses of OFF-center ganglion cells have been shown to be markedly reduced or abolished by a dopamine antagonist. This effect of a dopamine antagonist was recently shown to be reversed by the glycine antagonist strychnine and by compounds that elevate intracellular cAMP levels. The present study was conducted to determine whether strychnine and cAMP-elevating compounds could bring out the surround ON responses in OFF-center ganglion cells that are diminished upon dark adaptation. Extracellular recordings of OFF-center brisk ganglion cells were made from isolated, superfused retinal preparations. During the course of dark adaptation, the surround On responses of many cells decreased markedly.Application in both brisk-transient and brisk-sustained OFF-center ganglion cells. The center OFF responses of these cells, on the other hand, were not enhanced by strychnine. Of the cAMP-elevating compounds tested, 8-(4-chlorophenylthio) cyclic AMP was the most effective in bringing out the surround ON responses in dark-adapted OFF-center ganglion cells. The findings from this study suggest that under dark-adapted conditions glycinergic neurons inhibit the surround component of OFF-center ganglion cells. The release of glycine from these neurons is suggested to be regulated by a cAMP-dependent mechanism.

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Spatially restricted electrical activation of retinal ganglion cells in the rabbit retina by hexapolar electrode return configuration

Journal of Neural Engineering ◽

10.1088/1741-2560/10/3/036013 ◽

2013 ◽

Vol 10 (3) ◽

pp. 036013 ◽

Cited By ~ 26

Author(s):

Amgad G Habib ◽

Morven A Cameron ◽

Gregg J Suaning ◽

Nigel H Lovell ◽

John W Morley

Keyword(s):

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Electrical Activation ◽

Rabbit Retina ◽

Retinal Ganglion

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Synaptic inputs from identified bipolar and amacrine cells to a sparsely branched ganglion cell in rabbit retina

Visual Neuroscience ◽

10.1017/s0952523819000014 ◽

2019 ◽

Vol 36 ◽

Cited By ~ 4

Author(s):

Andrea S. Bordt ◽

Diego Perez ◽

Luke Tseng ◽

Weiley Sunny Liu ◽

Jay Neitz ◽

...

Keyword(s):

Ganglion Cell ◽

Retinal Ganglion Cells ◽

Amacrine Cell ◽

Ganglion Cells ◽

Amacrine Cells ◽

Bipolar Cells ◽

Rabbit Retina ◽

Retinal Ganglion ◽

Synaptic Inputs ◽

Class Iv

AbstractThere are more than 30 distinct types of mammalian retinal ganglion cells, each sensitive to different features of the visual environment. In rabbit retina, they can be grouped into four classes according to their morphology and stratification of their dendrites in the inner plexiform layer (IPL). The goal of this study was to describe the synaptic inputs to one type of Class IV ganglion cell, the third member of the sparsely branched Class IV cells (SB3). One cell of this type was partially reconstructed in a retinal connectome developed using automated transmission electron microscopy (ATEM). It had slender, relatively straight dendrites that ramify in the sublamina a of the IPL. The dendrites of the SB3 cell were always postsynaptic in the IPL, supporting its identity as a ganglion cell. It received 29% of its input from bipolar cells, a value in the middle of the range for rabbit retinal ganglion cells studied previously. The SB3 cell typically received only one synapse per bipolar cell from multiple types of presumed OFF bipolar cells; reciprocal synapses from amacrine cells at the dyad synapses were infrequent. In a few instances, the bipolar cells presynaptic to the SB3 ganglion cell also provided input to an amacrine cell presynaptic to the ganglion cell. There was apparently no crossover inhibition from narrow-field ON amacrine cells. Most of the amacrine cell inputs were from axons and dendrites of GABAergic amacrine cells, likely providing inhibitory input from outside the classical receptive field.

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Properties of stimulus-dependent synchrony in retinal ganglion cells

Visual Neuroscience ◽

10.1017/s0952523807070757 ◽

2007 ◽

Vol 24 (6) ◽

pp. 827-843 ◽

Cited By ~ 4

Author(s):

SUSMITA CHATTERJEE ◽

DAVID K. MERWINE ◽

FRANKLIN R. AMTHOR ◽

NORBERTO M. GRZYWACZ

Keyword(s):

Ganglion Cell ◽

Retinal Ganglion Cells ◽

Functional Role ◽

Ganglion Cells ◽

Receptive Fields ◽

Rabbit Retina ◽

Retinal Ganglion ◽

Spike Synchrony ◽

Full Field ◽

Dependent Correlation

Neighboring retinal ganglion cells often spike synchronously, but the possible function and mechanism of this synchrony is unclear. Recently, the strength of the fast correlation between ON-OFF directionally selective cells of the rabbit retina was shown to be stimulus dependent. Here, we extend that study, investigating stimulus-dependent correlation among multiple ganglion-cell classes, using multi-electrode recordings. Our results generalized those for directionally selective cells. All cell pairs exhibiting significant spike synchrony did it for an extended edge but rarely for full-field stimuli. The strength of this synchrony did not depend on the amplitude of the response and correlations could be present even when the cells' receptive fields did not overlap. In addition, correlations tended to be orientation selective in a manner predictable by the relative positions of the receptive fields. Finally, extended edges and full-field stimuli produced significantly greater and smaller correlations than predicted by chance respectively. We propose an amacrine-network model for the enhancement and depression of correlation. Such an apparently purposeful control of correlation adds evidence for retinal synchrony playing a functional role in vision.

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Mechanism and site of action of a dopamine D1 antagonist in the rabbit retina

Visual Neuroscience ◽

10.1017/s0952523800009901 ◽

1989 ◽

Vol 3 (6) ◽

pp. 573-585 ◽

Cited By ~ 27

Author(s):

Ralph J. Jesen

Keyword(s):

Adenylate Cyclase ◽

Ganglion Cells ◽

Excitatory Amino Acid ◽

Sch 23390 ◽

Amacrine Cells ◽

Intracellular Camp ◽

Rabbit Retina ◽

Pharmacological Agents ◽

Evoked Activity ◽

Camp Levels

AbstractDopamine D1 antagonists have been shown to alter drastically the spontaneous and light-evoked activity of ganglion cells in the rabbit retina (Jensen & Daw, 1984, 1986). A major target of dopaminergic neurons in mammalian retinas appears to be rod All amacrine cells (Pourcho, 1982; Voigt & Wässle, 1987). In the present study, the following questions were addressed: (1) Do dopamine D1 antagonists alter the activity of ganglion cells through actions primarily on rod All amacrine cells? (2) Are the effects of dopamine D1 antagonists on ganglion cells due to an inhibition of dopamine-stimulated adenylate cyclase activity?Using an isolated, superfused retinal preparation, the ability of several pharmacological agents to counteract the physiological effects of the dopamine D1 antagonist (+)-SCH 23390 on rabbit ganglion cells was examined. The glycine antagonist strychnine abolished the effects of (+)-SCH 23390 on the spontaneous and light-evoked activity of OFF-center ganglion cells, whereas the excitatory amino-acid antagonist kynurenic acid abolished the effects of (+)-SCH 23390 on the spontaneous and light-evoked activity of ON-center ganglion cells. The findings obtained with these antagonists can be explained in terms of the known synaptic connections of All amacrine cells.Both 8-(4-chlorophenylthio) cyclic AMP, a membrane-permeable cAMP analog, and forskolin, an activator of adenylate cyclase, reversed the effects of (+)-SCH 23390 on the spontaneous and light-evoked activity of OFF-center ganglion cells but not ON-center ganglion cells. These findings suggest that the effects of dopamine D1 antagonists on OFF-center ganglion cells are due to an inhibition of dopamine-stimulated adenylate cyclase, with the ensuing lowering of cellular cAMP levels. The effects of dopamine D1 antagonists on ON-center ganglion cells appear, however, to be independent of intracellular cAMP levels.

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Management of glaucoma with neuroprotective drug

Bangladesh Journal of Medical Science ◽

10.3329/bjms.v9i4.6685 ◽

1970 ◽

Vol 9 (4) ◽

pp. 199-203

Author(s):

Md Nurul Islam

Keyword(s):

Cell Death ◽

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Medical Science ◽

Retinal Ganglion ◽

Progressive Loss ◽

Independent Mechanism ◽

Pressure Independent ◽

Neuro Protection ◽

Dependent Mechanism

Glaucoma is an optic neuropathy characterized by progressive loss of retinal ganglion cells (RGCs). Death of ganglion cells is not always only pressure dependent mechanism but also have several pressure independent mechanism that establish a cascade of changes that ultimately leads to cell death. Neuro- protection is a process that attempt to preserve the cells that were spared during initial insult, but are still vulnerable to damage. Although not yet available, a neuroprotective agent would be great use that rescue neurons already compromised or that promote regrowth of axonal or dendritic connection to restore function. This review based on literature, giving the idea of varies mechanism of RGC death delineated by research and discussed some pharmacological agent believed to have a neuroprotective role in glaucoma. DOI: 10.3329/bjms.v9i4.6685Bangladesh Journal of Medical Science Vol.09 No.4 July 2010 pp.199-203

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