Visual resolution and receptive field size: examination of two kinds of cat retinal ganglion cell

Science ◽  
1979 ◽  
Vol 205 (4410) ◽  
pp. 1015-1017 ◽  
Author(s):  
B. Cleland ◽  
T. Harding ◽  
U Tulunay-Keesey
Keyword(s):  
Receptive Field ◽  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
Field Size ◽  
Retinal Ganglion ◽  
Receptive Field Size ◽  
Visual Resolution

Compensation for population size mismatches in the hamster retinotectal system: Alterations in the organization of retinal projections

1991 ◽  
Vol 6 (3) ◽  
pp. 271-281 ◽  
Author(s):  
S.L. Pallas ◽  
B.L. Finlay
Keyword(s):  
Receptive Field ◽  
Injection Site ◽  
Ganglion Cell ◽  
Retinal Ganglion Cells ◽  
Ganglion Cells ◽  
Fragment Size ◽  
Field Size ◽  
Retinal Ganglion ◽  
Receptive Field Size ◽  
Receptive Field Properties

AbstractUnilateral partial ablation of the superior colliculus in the hamster results in a compression of the retinotopic map onto the remaining tectal fragment. In a previous electrophysiological study (Pallas & Finlay, 1989a), we demonstrated that receptive-field properties of single tectal units (including receptive-field size) remain unchanged, despite the increased afferent/target convergence ratios in the compressed tecta. The present study was done to investigate the mechanism that produces increased convergence from retina to tectum at the population level while maintaining apparent stability of convergence at the single neuron level. We injected comparable quantities of horseradish peroxidase into the tecta of normal adult hamsters and adult hamsters that had received neonatal partial tectal ablations of varying magnitude. We then compared the area of retina backfilled from the injection and the number and density of labeled retinal ganglion cells within it to the size of the remaining tectal fragment.As expected from earlier anatomical (Jhaveri & Schneider, 1974) and physiological (Finlay et al., 1979a; Pallas & Finlay, 1989a) studies demonstrating compression of the retinotectal projection, we found that the area of retina labeled from a single tectal injection site increases linearly with decreasing tectal fragment size. However, for fragment sizes down to 30% of normal, total number of retinal ganglion cells projecting to the injection site remains in or above the normal range. For large lesions (less than 30% of tectum remaining), total number of labeled retinal ganglion cells declines from normal, despite the fact that a larger absolute area of retina is represented on each unit of tectum under these conditions. Comparison of retinal ganglion cell density with tectal fragment size shows an initial decline with decreasing fragment size, which becomes sharper with very large lesions (small tectal fragments).The maintenance of the normal number of retinal ganglion cells innervating each patch of tectum could be accomplished by an elimination of the tectal collaterals of some retinal ganglion cells. Our results suggest that, in addition to collateral elimination, reduction in the size of ganglion cell arbors is occurring, since the peak density of backfilled ganglion cells declines less rapidly than backfilled retinal area increases, especially for small lesions. However, arbor reduction and collateral elimination must occur in such a way that individual tectal cells represent the same amount of visual space as normal.Thus, collateral elimination and arbor reduction are two mechanisms that operate to maintain afferent/target convergence ratios (and thus receptive-field properties) over large variations in afferent availability. This compensation may occur through an activity-dependent stabilization mechanism that does not change its selectivity even when excess afferents are available. For very large lesion sizes, receptive-field size and innervating ganglion cell number and density are not preserved, thus demonstrating a limit to the afferent/target matching mechanism. The same ontogenetic mechanisms might provide a buffer for normal variations in afferent populations, and could help to align topographic maps with differing numbers of afferents.

scholarly journals Retinal ganglion cell dysfunction in mice following acute intraocular pressure is exacerbated by P2X7 receptor knockout

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Anna Y. M. Wang ◽  
Vickie H. Y. Wong ◽  
Pei Ying Lee ◽  
Bang V. Bui ◽  
Stefanie Dudczig ◽  
...  
Keyword(s):  
Intraocular Pressure ◽  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
P2x7 Receptor ◽  
Field Size ◽  
Multielectrode Arrays ◽  
Retinal Ganglion ◽  
Post Injury ◽  
Genetic Ablation ◽  
Iop Elevation

AbstractThere is increasing evidence for the vulnerability of specific retinal ganglion cell (RGC) types in those with glaucoma and in animal models. In addition, the P2X7-receptor (P2X7-R) has been suggested to contribute to RGC death following stimulation and elevated IOP, though its role in RGC dysfunction prior to death has not been examined. Therefore, we examined the effect of an acute, non-ischemic intraocular pressure (IOP) insult (50 mmHg for 30 min) on RGC function in wildtype mice and P2X7-R knockout (P2X7-KO) mice. We examined retinal function using electroretinogram recordings and individual RGC responses using multielectrode arrays, 3 days following acute IOP elevation. Immunohistochemistry was used to examine RGC cell death and P2X7-R expression in several RGC types. Acute intraocular pressure elevation produced pronounced dysfunction in RGCs; whilst other retinal neuronal responses showed lesser changes. Dysfunction at 3 days post-injury was not associated with RGC loss or changes in receptive field size. However, in wildtype animals, OFF-RGCs showed reduced spontaneous and light-elicited activity. In the P2X7-KO, both ON- and OFF-RGC light-elicited responses were reduced. Expression of P2X7-R in wildtype ON-RGC dendrites was higher than in other RGC types. In conclusion, OFF-RGCs were vulnerable to acute IOP elevation and their dysfunction was not rescued by genetic ablation of P2X7-R. Indeed, knockout of P2X7-R also caused ON-RGC dysfunction. These findings aid our understanding of how pressure affects RGC function and suggest treatments targeting the P2X7-R need to be carefully considered.

scholarly journals Bicycronic construct for optogenetic prosthesis of ganglion cell receptive field of degenerated retina

2019 ◽  
Vol 486 (2) ◽  
pp. 258-261
Author(s):  
L. E. Petrovskaya ◽  
M. V. Roshchin ◽  
G. R. Smirnova ◽  
D. E. Kolotova ◽  
P. M. Balaban ◽  
...  
Keyword(s):  
Receptive Field ◽  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
Distinctive Feature ◽  
Action Potentials ◽  
Ganglion Cells ◽  
Retinal Ganglion ◽  
Light Stimulation ◽  
Genetic Construct ◽  
Stimulation Of

For the purpose of optogenetic prosthetics of the receptive field of the retinal ganglion cell, we have created a bicistronic genetic construct that carries genes of excitatory (channelorhodopsin2) and inhibitory (anionic channelorhodopsin) rhodopsins. A distinctive feature of this construct is the combination of two genes into one construct with the mutant IRES inserted between them, which ensures precise ratio of the expression levels of the first and second gene in each transfected cell. It was found that the illumination of the central part of transfected neuron with light with a wavelength of 470 nm causes the generation of action potentials in the cell. At the same time, light stimulation of the periphery of the neuron causes cessation of the generation of action potentials. Thus, we were able to simulate the ON-OFF interaction of the receptive field of the retinal ganglion cell using optogenetic methods. Theoretically, this construction can be used for optogenetic prosthetics of degenerative retina in case of its delivery to ganglion cells using lentiviral vectors.

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