Processing of S-cone signals in the inner plexiform layer of the mammalian retina

AbstractColor information is encoded by two parallel pathways in the mammalian retina. One pathway compares signals from long- and middle-wavelength sensitive cones and generates red-green opponency. The other compares signals from short- and middle-/long-wavelength sensitive cones and generates blue-green (yellow) opponency. Whereas both pathways operate in trichromatic primates (including humans), the fundamental, phylogenetically ancient color mechanism shared among most mammals is blue-green opponency. In this review, we summarize the current understanding of how signals from short-wavelength sensitive cones are processed in the primate and nonprimate mammalian retina, with a focus on the inner plexiform layer where bipolar, amacrine, and ganglion cell processes interact to facilitate the generation of blue-green opponency.

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Understanding Retinal Microcircuitry: Then to Now

Handbook of Brain Microcircuits ◽

10.1093/med/9780190636111.003.0022 ◽

2017 ◽

pp. 273-284

Author(s):

Frank S. Werblin ◽

John E. Dowling

Keyword(s):

Electron Microscope ◽

Ganglion Cell ◽

Ganglion Cells ◽

Plexiform Layer ◽

Cell Types ◽

The Other ◽

Inner Plexiform Layer ◽

Single Neurons ◽

History Of ◽

Synaptic Circuitry

This chapter focuses on the history of understanding retinal microcircuitry. To understand the microcircuitry underlying the responses of all ganglion cell types that exist in vertebrate retinas will require much work. We have a fairly good notion of how ON and OFF center ganglion cells are established by excitatory and inhibitory inputs in the outer plexiform layer (OPL) and inner plexiform layer (IPL), as well as how direction selection (DS) properties are imparted to ON-OFF ganglion cells in the IPL; but we have only fragmentary information regarding the microcircuitry of the other ganglion cell types. We do know where to look—along the various strata in the IPL. With electron microscope methods to determine synaptic circuitry and methods to record responses of single neurons in a circuit available, the microcircuitry of the strata in the IPL can be elucidated.

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Organization of the primate retina: electron microscopy

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1966.0086 ◽

1966 ◽

Vol 166 (1002) ◽

pp. 80-111 ◽

Cited By ~ 526

Keyword(s):

Electron Microscopy ◽

Ganglion Cell ◽

Bipolar Cell ◽

Amacrine Cell ◽

Receptor Cell ◽

Plexiform Layer ◽

Cell Physiology ◽

Inner Plexiform Layer ◽

Synaptic Contacts ◽

Cell Processes

The retinae of monkey and man have been studied by electron microscopy to identify cell types, their processes and synaptic contacts. In the inner plexiform layer, the morphological characteristics of the three types of cells (bipolar, ganglion and amacrine) are described and seven synaptic relationships are identified. The bipolar terminals contain ribbons at points of synaptic contact, and, at these points, there are typically two postsynaptic processes, one a ganglion cell dendrite, the other an amacrine cell process. This synaptic arrangement is here termed a dyad. The amacrine cell processes themselves make synaptic contacts with ganglion cell dendrites and somata, other amacrine cell processes, and, most frequently, with the bipolar cell terminals. Often, the amacrine-bipolar contact is adjacent to a bipolar-amacrine junction, forming a reciprocal synaptic arrangement between the bipolar and the amacrine. In the more peripheral retina, large bipolar cell terminals (probably of rod bipolars) are occasionally observed adjacent to the perikarya of the ganglion cells. At these junctions, areas of fusion between the plasma membranes are seen, suggesting that such axosomatic junctions could be electrical. In the outer plexiform layer, synapses have been identified only in the receptor cell bases where receptor cells contact bipolar and horizontal cell processes. Synaptic contacts of the horizontal cells have not been clearly identified, but their strategic terminations in the receptor cell ending are described and interpreted as possibly synaptic. A model of the retina, based on the described anatomy, is presented and correlated with ganglion cell physiology.

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Synaptic circuitry of neuropeptide-containing amacrine cells in the retina of the cane toad, Bufo marinus

Visual Neuroscience ◽

10.1017/s0952523800009470 ◽

1995 ◽

Vol 12 (5) ◽

pp. 919-927 ◽

Cited By ~ 9

Author(s):

Bao-Song Zhu ◽

Ian Gibbins

Keyword(s):

Ganglion Cell ◽

Bipolar Cell ◽

Amacrine Cell ◽

Plexiform Layer ◽

Amacrine Cells ◽

Bufo Marinus ◽

Inner Plexiform Layer ◽

Cane Toad ◽

Synaptic Inputs ◽

Cell Processes

AbstractSynaptic connections of amacrine cells with substance P-like or neuropeptide Y-like immunoreactivity (SP-LI or NPY-LI) in the retina of the cane toad, Bufo marinus, were investigated using ultrastructural immunocytochemistry. The perikarya of SP-LI or NPY-LI amacrine cells were located in the innermost row of the inner nuclear layer. The synapses associated with SP-LI amacrine cells were distributed mainly in sublaminae 3 and 4 with about 10% in sublamina 1 of the inner plexiform layer. The synapses formed by NPY-LI amacrine cells were found in sublaminae 1, 2, and 4 with approximately equal frequency. Of a total of 175 SP-LI profiles, 56% were in presynaptic positions and 44% in postsynaptic positions. The synaptic inputs to SP-LI profiles predominantly derived from other unlabeled amacrine cell dendrites, and to a lesser extent, from bipolar cell terminals. The majority of synaptic outputs from SP-LI amacrine cell dendrites were directed onto unlabeled amacrine cell processes. The SP-LI profiles also made synapses onto bipolar cell terminals and formed synapses onto presumed ganglion cell dendrites. Of a total of 200 NPY-LI profiles, 48% were in presynaptic positions and 52% in postsynaptic positions. The profiles of NPY-LI amacrine cells mainly received their synaptic inputs from other unlabeled amacrine cell processes, and to a lesser extent, from bipolar cell terminals. The majority of NPY-LI amacrine cell profiles gave their synaptic outputs onto unlabeled amacrine cell dendrites, and others formed synapses onto presumed ganglion cell processes. These results suggest that these two populations of neuropeptide-containing amacrine cells in the Bufo retina are involved in different synaptic circuits.

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Ganglion Cell-Inner Plexiform Layer, Peripapillary Retinal Nerve Fiber Layer, and Macular Thickness in Eyes with Myopicβ-Zone Parapapillary Atrophy

Journal of Ophthalmology ◽

10.1155/2016/3746791 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Jin-woo Kwon ◽

Jin A. Choi ◽

Jung-sub Kim ◽

Tae Yoon La

Keyword(s):

Ganglion Cell ◽

Nerve Fiber ◽

Retinal Nerve Fiber Layer ◽

Plexiform Layer ◽

The Other ◽

Inner Plexiform Layer ◽

Fiber Layer ◽

Nerve Fiber Layer ◽

Significant Difference ◽

Parapapillary Atrophy

Purpose. To assess the correlations of myopicβ-zone parapapillary atrophy (β-PPA) with the optic nerve head (ONH) and retina.Methods. We selected 27 myopic patients who showed prominentβ-PPA in one eye and noβ-PPA in the other eye. We studied their macula, macular ganglion cell-inner plexiform layer (mGCIPL), peripapillary retinal nerve fiber layer (pRNFL) thickness, and ONH parameters using optical coherence tomography.Results. The average of five out of six sectors and minimum values of mGCIPL thicknesses in eyes with prominentβ-PPA discs were significantly less than those of the control eyes. The results of clock-hour sector analyses showed significant differences for pRNFL thickness in one sector. In the ONH analyses, no significant difference was observed between myopicβ-PPA and control eyes. The macular thickness of theβ-PPA eyes was thinner than control eyes in all sectors. There was a significant difference between the two groups in three sectors (the inner superior macula, inner temporal macula, and inner inferior macula) but there was no significant difference in the other sectors, including the fovea.Conclusions. The myopicβ-PPA eyes showed thinner mGCIPL, parafovea, and partial pRNFL layers compared with myopic eyes withoutβ-PPA.

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Displaced horizontal cells and biplexiform horizontal cells in the mammalian retina

Visual Neuroscience ◽

10.1017/s0952523800005988 ◽

1989 ◽

Vol 3 (5) ◽

pp. 483-488 ◽

Cited By ~ 22

Author(s):

L. C. L. Silveira ◽

E. S. Yamada ◽

C. W. Picanço-Diniz

Keyword(s):

Ganglion Cell ◽

Ganglion Cell Layer ◽

Cell Layer ◽

Horizontal Cell ◽

Plexiform Layer ◽

Cell Types ◽

Horizontal Cells ◽

Inner Plexiform Layer ◽

Retinal Periphery ◽

Mammalian Retina

AbstractWe have used the neurofibrillar method of Gros-Schultze to stain the axonless horizontal cells of capybara, agouti, cat, and rabbit retinae. In all of these species, we have found two unusual horizontal cell morphologies: displaced horizontal cells and biplexiform horizontal cells. The displaced horizontal cells have perikarya located in the ganglion cell layer and dendrites branching in the inner plexiform layer. Many dendrites take an ascending trajectory to branch in the outer plexiform layer. The biplexiform horizontal cells are normally placed horizontal cells with descending processes that branch in the inner plexiform layer. Both cell types occur mainly in the retinal periphery, near the ora serrata. They are more numerous in the capybara retina, where they represent as much as 50% of the axonless horizontal cells of the retinal periphery.

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Synaptic input to an ON parasol ganglion cell in the macaque retina: A serial section analysis

Visual Neuroscience ◽

10.1017/s0952523802192078 ◽

2002 ◽

Vol 19 (3) ◽

pp. 299-305 ◽

Cited By ~ 23

Author(s):

DAVID W. MARSHAK ◽

ELIZABETH S. YAMADA ◽

ANDREA S. BORDT ◽

WENDY C. PERRYMAN

Keyword(s):

Ganglion Cell ◽

Bipolar Cell ◽

Amacrine Cell ◽

Ganglion Cells ◽

Plexiform Layer ◽

Amacrine Cells ◽

Bipolar Cells ◽

Inhibitory Input ◽

Inner Plexiform Layer ◽

Cell Processes

A labeled ON parasol ganglion cell from a macaque retina was analyzed in serial, ultrathin sections. It received 13% of its input from diffuse bipolar cells. These directed a large proportion of their output to amacrine cells but received a relatively small proportion of their amacrine cell input via feedback synapses. In these respects, they were similar to the DB3 bipolar cells that make synapses onto OFF parasol cells. Bipolar cell axons that contacted the ON parasol cell in stratum 4 of the inner plexiform layer always made synapses onto the dendrite, and therefore, the number of bipolar cell synapses onto these ganglion cells could be estimated reliably by light microscopy in the future. Amacrine cells provided the majority of inputs to the ON parasol cell. Only a few of the presynaptic amacrine cell processes received inputs from the same bipolar cells as the parasol cells, and most of the presynaptic amacrine cell processes did not receive any inputs at all within the series. These findings suggest that most of the inhibitory input to the ON parasol cell originates from other areas of the retina. Amacrine cells presynaptic to the parasol ganglion cell interacted very infrequently with other neurons in the circuit, and therefore, they would be expected to act independently, for the most part.

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