Topographies of retinal cone photoreceptors in two Australian 
marsupials

Microspectrophotometry indicates the presence of at least three cone visual pigments in two Australian marsupials, the fat-tailed dunnart (Sminthopsis crassicaudata) and honey possum (Tarsipes rostratus). Here we have examined the distribution of cone types using antisera, JH455 and JH492, that recognize short-wavelength-sensitive (SWS) and medium-to-long-wavelength-sensitive (M/LWS) cone opsins, respectively. SWS cones were concentrated in dorso-temporal retina in the dunnart with a shallow decreasing gradient extending to the periphery (2300–1500/mm2). In the honey possum, SWS cones showed a uniform distribution (2700/mm2), except for a slight increase in a narrow peripheral band (3100/mm2). In both species, M/LWS cones dominated and their distributions were similar to those of retinal ganglion cells: a horizontal streak in the dunnart (31,000–21,000/mm2) and a shallow mid-ventral to peripheral gradient in the honey possum (37,000–26,000/mm2). A low number of cones remained unlabeled when the antisera were combined revealing further minority cone population(s). We discuss cone distributions in relation to visual capabilities and requirements of the species.

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No evidence for an S cone contribution to the human circadian response to light

10.1101/763359 ◽

2019 ◽

Author(s):

Manuel Spitschan ◽

Rafael Lazar ◽

Ebru Yetik ◽

Christian Cajochen

Keyword(s):

Retinal Ganglion Cells ◽

Short Wavelength ◽

Ganglion Cells ◽

Light Exposure ◽

Retinal Ganglion ◽

Long Wavelength ◽

Short Wavelength Light ◽

The Brain ◽

Wavelength Light

Exposure to even moderately bright, short-wavelength light in the evening can strongly suppress the production of melatonin and can delay our circadian rhythm. These effects are mediated by the retinohypothalamic pathway, connecting a subset of retinal ganglion cells to the circadian pacemaker in the suprachiasmatic nucleus (SCN) in the brain. These retinal ganglion cells directly express the photosensitive protein melanopsin, rendering them intrinsically photosensitive (ipRGCs). But ipRGCs also receive input from the classical photoreceptors — the cones and rods. Here, we examined whether the short-wavelength-sensitive (S) cones contribute to circadian photoreception by using lights which differed exclusively in the amount of S cone excitation by almost two orders of magnitude (ratio 1:83), but not in the excitation of long-wavelength-sensitive (L) and medium-wavelength-sensitive (M) cones, rods, and melanopsin. We find no evidence for a role of S cones in the acute alerting and melatonin supressing response to evening light exposure, pointing to an exclusive role of melanopsin in driving circadian responses.

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Investigating visual mechanisms underlying scene brightness

Lighting Research and Technology ◽

10.1177/1477153516628168 ◽

2016 ◽

Vol 49 (1) ◽

pp. 16-32 ◽

Cited By ~ 8

Author(s):

UC Besenecker ◽

JD Bullough

Keyword(s):

Retinal Ganglion Cells ◽

Spectral Sensitivity ◽

Short Wavelength ◽

Ganglion Cells ◽

Forced Choice ◽

Light Sources ◽

Retinal Ganglion ◽

Brightness Perception ◽

Light Levels ◽

Relative Brightness

Short-wavelength (<500 nm) output of light sources enhances scene brightness perception in the low-to-moderate photopic range. This appears to be partially explained by a contribution from short-wavelength cones. Recent evidence from experiments on humans suggests that intrinsically photosensitive retinal ganglion cells (ipRGCs) containing the photopigment melanopsin might also contribute to spectral sensitivity for scene brightness perception. An experiment was conducted to investigate this possibility at two different light levels, near 10 lx and near 100 lx. Subjects provided forced-choice brightness judgments and relative brightness magnitude judgments when comparing two different amber-coloured stimuli with similar chromaticities. A provisional brightness metric including an ipRGC contribution was able to predict the data with substantially smaller errors than a metric based on cone input only.

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Ganglion cells of a short-wavelength-sensitive cone pathway in New World monkeys: Morphology and physiology

Visual Neuroscience ◽

10.1017/s0952523899162138 ◽

1999 ◽

Vol 16 (2) ◽

pp. 333-343 ◽

Cited By ~ 46

Author(s):

LUIZ CARLOS L. SILVEIRA ◽

BARRY B. LEE ◽

ELIZABETH S. YAMADA ◽

JAN KREMERS ◽

DAVID M. HUNT ◽

...

Keyword(s):

Retinal Ganglion Cells ◽

Short Wavelength ◽

New World ◽

Ganglion Cells ◽

Dendritic Tree ◽

New World Monkeys ◽

Retinal Ganglion ◽

Old World ◽

Contrast Gain ◽

Cone Pathway

We have studied the morphology and physiology of retinal ganglion cells of a short-wavelength-sensitive cone (SWS-cone) pathway in dichromatic and trichromatic New World anthropoids, the capuchin monkey (Cebus apella) and tufted-ear marmoset (Callithrix jacchus). In Old World anthropoids, in which males and females are both trichromats, blue-ON/yellow-OFF retinal ganglion cells have excitatory SWS-cone and inhibitory middle- and long-wavelength-sensitive (MWS- and LWS-) cone inputs, and have been anatomically identified as small-field bistratified ganglion cells (SB-cells) (Dacey & Lee, 1994). Among retinal ganglion cells of New World monkeys, we find SB-cells which have very similar morphology to such cells in macaque and human; for example, the inner dendritic tree is larger and denser than the outer dendritic tree. We also find blue-on retinal ganglion cells of the capuchin to have physiological responses strongly resembling such cells of the macaque monkey retina; for example, responses were more sustained, with a gentler low frequency roll-off than MC-cells, and no evidence of contrast gain control. There was no difference between dichromatic and trichromatic individuals. The results support the view that SWS-cone pathways are similarly organized in New and Old World primates, consistent with the hypothesis that these pathways form a phylogenetically ancient color system.

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Cone and rod inputs to murine retinal ganglion cells: Evidence of cone opsin specific channels

Visual Neuroscience ◽

10.1017/s0952523805226172 ◽

2005 ◽

Vol 22 (6) ◽

pp. 893-903 ◽

Cited By ~ 33

Author(s):

BJORN EKESTEN ◽

PETER GOURAS

Keyword(s):

Spontaneous Activity ◽

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Low Frequency ◽

Opposite Polarity ◽

Retinal Ganglion ◽

Chromatic Contrast ◽

Cone Opsin ◽

Physiological Capacity ◽

Cone Opsins

To identify ultraviolet (UV) and middle- (M) wavelength-sensitive cone and rod signals in murine retinal ganglion cells, single ganglion cell responses were studied in anesthetized, light-adapted C57/BL6 mice with tungsten microelectrodes driven through the sclera and vitreous to the neural retina. One hundred fifty-four ganglion cells were examined in 43 retinas of 34 mice. The retina was stimulated with diffuse flashes and/or pulses of ultraviolet (360 nm) or green (520 nm) light in the presence and absence of a strong steady orange adapting light. Twelve ganglion cells were studied in the dark-adapted retina in order to identify the signals of rods. Three functionally different types of ganglion cells were found: (1) phasic responding cells (31%) with no spontaneous activity and large impulse amplitudes; (2) tonic responding cells (60%) with irregular, low frequency (5–10 Hz) spontaneous activity and smaller impulse amplitudes; and (3) metronome-like cells (9%) with regular, relatively high-frequency (20–40 Hz) spontaneous activity. A few cells (1%) had habituating responses. Every cell encountered was affected by diffuse stimulation. The more common two types were excited at either the ON or OFF or at both the ON and OFF phases of stimulation. Type III cells had weaker responses, sometimes only inhibited by turning off a light. In the light-adapted state, most cells received signals of the same polarity from UV- and M-cones but UV-cone inputs were usually more dominant, especially in ventral retina. A fraction of cells received signals from only UV- (18%) or only M- (3%) cones. In rare cases (2%) these cone inputs had an opposite polarity on the same cell. In the dark-adapted state, all cells were at least four or five logarithmic units more sensitive and more to green than ultraviolet light. The results indicate that co-expression of both UV-and M-cone opsins cannot be ubiquitous in murine retina. Some cones, especially UV cones, exist without the presence of any functional M-cone opsin. This must be the case to explain the presence of ganglion cells that receive inputs only from UV-cones and others that receive inputs of opposite polarity from UV- and M-cones. The results support the hypothesis that murine retina has the physiological capacity to relay signals to the brain that allow the sensing of chromatic contrast and color vision.

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Short-wavelength cone-opponent retinal ganglion cells in mammals

Visual Neuroscience ◽

10.1017/s095252381300031x ◽

2014 ◽

Vol 31 (2) ◽

pp. 165-175 ◽

Cited By ~ 23

Author(s):

DAVID W. MARSHAK ◽

STEPHEN L. MILLS

Keyword(s):

Retinal Ganglion Cells ◽

Short Wavelength ◽

Ganglion Cells ◽

Mammalian Species ◽

Plexiform Layer ◽

Amacrine Cells ◽

Opposite Polarity ◽

Bipolar Cells ◽

Retinal Ganglion ◽

Cone Bipolar Cells

AbstractIn all of the mammalian species studied to date, the short-wavelength-sensitive (S) cones and the S-cone bipolar cells that receive their input are very similar, but the retinal ganglion cells that receive synapses from the S-cone bipolar cells appear to be quite different. Here, we review the literature on mammalian retinal ganglion cells that respond selectively to stimulation of S-cones and respond with opposite polarity to longer wavelength stimuli. There are at least three basic mechanisms to generate these color-opponent responses, including: (1) opponency is generated in the outer plexiform layer by horizontal cells and is conveyed to the ganglion cells via S-cone bipolar cells, (2) inputs from bipolar cells with different cone inputs and opposite response polarity converge directly on the ganglion cells, and (3) inputs from S-cone bipolar cells are inverted by S-cone amacrine cells. These are not mutually exclusive; some mammalian ganglion cells that respond selectively to S-cone stimulation seem to utilize at least two of them. Based on these findings, we suggest that the small bistratified ganglion cells described in primates are not the ancestral type, as proposed previously. Instead, the known types of ganglion cells in this pathway evolved from monostratified ancestral types and became bistratified in some mammalian lineages.

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