scholarly journals Voltage-Gated Calcium Currents in Isolated Retinal Ganglion Cells of the Cat.

1991 ◽  
Vol 41 (1) ◽  
pp. 35-48 ◽  
Author(s):  
Makoto KANEDA ◽  
Akimichi KANEKO
Keyword(s):  
Retinal Ganglion Cells ◽  
Ganglion Cells ◽  
Calcium Currents ◽  
Retinal Ganglion ◽  
Voltage Gated

scholarly journals Acute Modulation of Voltage‐Gated Ca 2+ Channels in Retinal Ganglion Cells by Gabapentin

2012 ◽  
Vol 26 (S1) ◽  
Author(s):  
Spring R Farrell ◽  
Luis Perez Sevilla Mueller ◽  
Allison Sargoy ◽  
Nicholas Brecha ◽  
Steven Barnes
Keyword(s):  
Retinal Ganglion Cells ◽  
Ganglion Cells ◽  
Retinal Ganglion ◽  
Voltage Gated

scholarly journals Two Metabotropic γ-Aminobutyric Acid Receptors Differentially Modulate Calcium Currents in Retinal Ganglion Cells

1997 ◽  
Vol 110 (1) ◽  
pp. 45-58 ◽  
Author(s):  
Jian Zhang ◽  
Wen Shen ◽  
Malcolm M. Slaughter
Keyword(s):  
Retinal Ganglion Cells ◽  
Gaba Receptors ◽  
Gaba Receptor ◽  
Ganglion Cells ◽  
Calcium Currents ◽  
Gabab Receptors ◽  
Aminobutyric Acid ◽  
Retinal Ganglion ◽  
Wide Range ◽  
Prepulse Facilitation

Metabotropic γ-aminobutyric acid (GABA) receptors were studied in amphibian retinal ganglion cells using whole cell current and voltage clamp techniques. The aim was to identify the types of receptor present and their mechanisms of action and modulation. Previous results indicated that ganglion cells possess two ionotropic GABA receptors: GABAAR and GABACR. This study demonstrates that they also possess two types of metabotropic GABAB receptor: one sensitive to baclofen and another to cis-aminocrotonic acid (CACA). The effects of these selective agonists were blocked by GDP-β-S. Baclofen suppressed an ω-conotoxin–GVIA-sensitive barium current, and this action was reversed by prepulse facilitation, indicative of a direct G-protein pathway. The effect of baclofen was also partially occluded by agents that influence the protein kinase A (PKA) pathway. But the effect of PKA activation was unaffected by prepulse facilitation, indicating PKA acted through a parallel pathway. Calmodulin antagonists reduced the action of baclofen, whereas inhibitors of calmodulin phosphatase enhanced it. Antagonists of internal calcium release, such as heparin and ruthenium red, did not affect the baclofen response. Thus, the baclofen-sensitive receptor may respond to influx of calcium. The CACA-sensitive GABA receptor reduced current through dihydropyridine-sensitive channels. Sodium nitroprusside and 8-bromo-cGMP enhanced the action of CACA, indicating that a nitric oxide system can up-regulate this receptor pathway. CACA-sensitive and baclofen-sensitive GABAB receptors reduced spike activity in ganglion cells. Overall, retinal ganglion cells possess four types of GABA receptor, two ionotropic and two metabotropic. Each has a unique electrogenic profile, providing a wide range of neural integration at the final stage of retinal information processing.

Signal shaping by voltage-gated currents in retinal ganglion cells

1992 ◽  
Vol 574 (1-2) ◽  
pp. 217-223 ◽  
Author(s):  
Peter Mobbs ◽  
Karen Everett ◽  
Alison Cook
Keyword(s):  
Retinal Ganglion Cells ◽  
Ganglion Cells ◽  
Retinal Ganglion ◽  
Voltage Gated

scholarly journals Voltage-gated calcium channel subunit α2δ-3 shapes light responses of mouse retinal ganglion cells mainly in low and moderate light levels

2020 ◽  
Author(s):  
Hartwig Seitter ◽  
Vithiyanjali Sothilingam ◽  
Boris Benkner ◽  
Marina Garcia Garrido ◽  
Alexandra Kling ◽  
...  
Keyword(s):  
Calcium Channels ◽  
Retinal Ganglion Cells ◽  
Ganglion Cells ◽  
Horizontal Cell ◽  
Gaussian White Noise ◽  
Retinal Ganglion ◽  
Visual Responses ◽  
Electrode Arrays ◽  
Voltage Gated ◽  
Voltage Gated Calcium Channels

AbstractLittle is known about the function of the auxiliary α2δ subunits of voltage-gated calcium channels in the retina. We investigated the role of α2δ-3 (Cacna2d3) using a mouse in which α2δ-3 was knocked out by LacZ insertion. Behavior experiments indicated a normal optokinetic reflex in α2δ-3 knockout animals. Strong expression of α2δ-3 could be localized to horizontal cells using the LacZ-reporter, but horizontal cell mosaic and currents carried by horizontal cell voltage-gated calcium channels were unchanged by the α2δ-3 knockout. In vivo electroretinography revealed unaffected photoreceptor activity and signal transmission to depolarizing bipolar cells. We recorded visual responses of retinal ganglion cells with multi-electrode arrays in scotopic to photopic luminance levels and found subtle changes in α2δ-3 knockout retinas. Spontaneous activity in OFF ganglion cells was elevated in all luminance levels. Differential response strength to high- and low-contrast Gaussian white noise was compressed in ON ganglion cells during mesopic ambient luminance and in OFF ganglion cells during scotopic and mesopic ambient luminances. In a subset of ON ganglion cells, we found a sharp increase in baseline spiking after the presentation of drifting gratings in scotopic luminance. This increase happened after gratings of different spatial properties in knockout compared to wild type retinas. In a subset of ON ganglion cells of the α2δ-3 knockout, we found altered delays in rebound-like spiking to full-field contrast steps in scotopic luminance. In conclusion, α2δ-3 seems to participate in shaping visual responses mostly within brightness regimes when rods or both rods and cones are active.

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