Laterally horizontal and amacrine cells retinal horizontal cells. Medical search. Frequent questions

The outermost layer of the retina, the retinal pigment epithelium, is tightly attached to the choroid. (medscape.com)
The retina, with the exception of the blood vessels coursing through it, is transparent to the examiner up to its outer layer, the retinal pigment epithelium. (medscape.com)
The examiner sees the neurosensory retina against the background orange color of the melanin containing retinal pigment epithelium and blood-filled choroidal layer of the eye. (medscape.com)
There is a potential space between the neurosensory retina and the retinal pigment epithelium. (medscape.com)
In a retinal detachment, this space fills with fluid and detaches the neurosensory retina from the underlying retinal pigment epithelium. (medscape.com)
Squid eyes do not have an analog of the vertebrate retinal pigment epithelium (RPE). (wikipedia.org)
A radial section of a portion of the retina reveals that the ganglion cells (the output neurons of the retina) lie innermost in the retina closest to the lens and front of the eye, and the photosensors (the rods and cones) lie outermost in the retina against the pigment epithelium and choroid. (org.es)
receptor cells nourished by pigment epithelium II. (9dok.org)

Amacrine cells are inhibitory neurons, and they project their dendritic arbors onto the inner plexiform layer (IPL), they interact with retinal ganglion cells, and bipolar cells or both of these. (wikipedia.org)
The neural retina consists of several layers of neurons interconnected by synapses and is supported by an outer layer of pigmented epithelial cells. (wikipedia.org)
Neural signals from the rods and cones undergo processing by other neurons, whose output takes the form of action potentials in retinal ganglion cells whose axons form the optic nerve. (wikipedia.org)
The vertebrate retina is inverted in the sense that the light-sensing cells are in the back of the retina, so that light has to pass through layers of neurons and capillaries before it reaches the photosensitive sections of the rods and cones. (wikipedia.org)
The optic nerve contains the ganglion cell axons running to the brain and, additionally, incoming blood vessels that open into the retina to vascularize the retinal layers and neurons (Fig. 1.1). (org.es)
Horizontal cell actions are in turn tuned by neuromodulators released by other retinal neurons. (org.es)
However, later intracellular marking techniques, in which dyes were injected from the electrode tips into the cytoplasm of the recorded neuron, revealed that horizontal cells, second order neurons postsynaptic to cones, were the source of the S-potentials (3, 4). (org.es)
Horizontal cells are second order neurons contacting photoreceptors directly all across the plane of the retina's outer plexiform layer. (org.es)
Now we know horizontal cells to be true neurons that make true, if unique, synapses and exhibit most of the structural and ultrastructural characteristics of neurons. (org.es)
Research has shown that the signal molecule, sonic hedgehog, that is produced in retinal ganglion neurons plays a role in this development. (veteriankey.com)

GABAergic amacrine cells are usually wide field amacrine cells and are found in the ganglion cell layer (GCL) and the inner nuclear layer (INL). (wikipedia.org)
The outer nuclear layer contains cell bodies of the rods and cones, the inner nuclear layer contains cell bodies of the bipolar, horizontal and amacrine cells and the ganglion cell layer contains cell bodies of ganglion cells and displaced amacrine cells. (org.es)

Amacrine cells are interneurons in the retina. (wikipedia.org)
Medium field amacrine cells also contribute to vertical communication in the cells of the retina, but much of their overall function is still unknown. (wikipedia.org)
Similarly, wide field amacrine cells are hard to research and even discover because they span the entire retina so there aren't many of them. (wikipedia.org)
Retinal nerve fibers exit the eye through the optic nerve, located nasally and on the same plane as the anatomical center of the retina. (medscape.com)
Assuming that the ocular media (cornea, anterior chamber, lens, and vitreous) are not cloudy, the living retina can be examined using a direct or indirect ophthalmoscope or a retinal lens at the slit lamp. (medscape.com)
In addition, the retina may be photographed using a retinal camera. (medscape.com)
therefore, the optic nerve must cross through the retina en route to the brain. (wikipedia.org)
A simplistic wiring diagram of the retina emphasizes only the sensory photoreceptors and the ganglion cells with a few interneurons connecting the two cell types such as seen in Figure 2. (org.es)
When an anatomist takes a vertical section of the retina and processes it for microscopic examination it becomes obvious that the retina is much more complex and contains many more nerve cell types than the simplistic scheme (above) had indicated. (org.es)
It is immediately obvious that there are many interneurons packed into the central part of the section of retina intervening between the photoreceptors and the ganglion cells (Fig 3). (org.es)
The second neuropil of the retina, is the inner plexiform layer (IPL), and it functions as a relay station for the vertical-information-carrying nerve cells, the bipolar cells, to connect to ganglion cells (Figs. 7 and 8). (org.es)
This is due to the increased packing density of photoreceptors, particularly the cones, and their associated bipolar and ganglion cells in central retina compared with peripheral retina. (org.es)
The outer nuclear layer (ONL), composed of the cell bodies of the rods and cones is about the same thickness in central and peripheral retina. (org.es)
However in the peripheral the rod cell bodies outnumber the cone cell bodies while the reverse is true for central retina. (org.es)
In central retina, the cones have oblique axons displacing their cell bodies from their synaptic pedicles in the outer plexiform layer (OPL). (org.es)
The inverted image of the objects projected to the retina, however can be processed at high resolution only at the central fovea, where light reaches the cone receptor cells directly. (9dok.org)
Horizontal cells are the interneurons of distal vertebrate retina. (org.es)
The actions of horizontal cells propagate forward in the retina, can be identified in the physiology of retinal ganglion cells, and in visual perception. (org.es)
At first, the cell type of origin for S-potentials was not really known other than that microelectrode tips were somewhere in the outer retina. (org.es)
In this chapter, we shall try to summarize our current knowledge of horizontal cells in the vertebrate retina. (org.es)
These cell types were first described as huge brick-like structures occupying much of the inner nuclear layer in the fish retina (27, 28). (org.es)

There are at least 33 different subtypes of amacrine cells based just on their dendrite morphology and stratification. (wikipedia.org)

Although the overlying neural tissue is partly transparent, and the accompanying glial cells have been shown to act as fibre-optic channels to transport photons directly to the photoreceptors, [7] [8] light scattering does occur. (wikipedia.org)
Although their photoreceptors contain a protein, retinochrome, that recycles retinal and replicates one of the functions of the vertebrate RPE, cephalopod photoreceptors are likely not maintained as well as in vertebrates, and that as a result, the useful lifetime of photoreceptors in invertebrates is much shorter than in vertebrates. (wikipedia.org)
Many forms of blindness result from the dysfunction or loss of retinal photoreceptors. (nature.com)
Moreover, the photoreceptors in our hiPSC-derived retinal tissue achieve advanced maturation, showing the beginning of outer-segment disc formation and photosensitivity. (nature.com)

These amacrine cells are sometimes known as nGnG amacrine cells, and it is thought that transcription factors that act on progenitors decide the fate of amacrine cells. (wikipedia.org)

Amacrine cells operate at inner plexiform layer (IPL), the second synaptic retinal layer where bipolar cells and retinal ganglion cells form synapses. (wikipedia.org)
All vertebrate retinas are composed of three layers of nerve cell bodies and two layers of synapses (Fig. 4). (org.es)

As mentioned above, there are several different ways to divide the many different types of amacrine cells into subtypes. (wikipedia.org)
They also generate color opponency in cones, bipolar cells, and chromatic horizontal-cell subtypes. (org.es)

Like horizontal cells, amacrine cells work laterally, but whereas horizontal cells are connected to the output of rod and cone cells, amacrine cells affect the output from bipolar cells, and are often more specialized. (wikipedia.org)
One important function of the AII amacrine cells is that they capture cellular input from rod bipolar cells and redistribute it to cone bipolar cells using the synaptic endings of cone bipolar cells as adaptors Around 15% of amacrine cells are neither GABAergic or glycinergic. (wikipedia.org)
The first area of neuropil is the outer plexiform layer (OPL) where connections between rod and cones, and vertically running bipolar cells and horizontally oriented horizontal cells occur (Figs. 5 and 6). (org.es)
Feedback signals adjust the gain of photoreceptor synaptic output, both as seen in the horizontal cells themselves and in the adjacent, proximally projecting bipolar cells. (org.es)
They generate spatial opponency in both cones and bipolar cells. (org.es)

Moreover, it has recently been shown that mouse and human ES cells can develop into a three-dimentional (3D) optic cup in culture that remarkably resembles the embryonic vertebrate eye 20 , 21 . (nature.com)
Since being first described in fish retinas, S-potentials have been recorded from retinal horizontal cells in all vertebrate classes. (org.es)

In addition, different varieties of horizontally- and vertically-directed amacrine cells, somehow interact in further networks to influence and integrate the ganglion cell signals. (org.es)

These are widely spreading amacrine cells, and they diffusely release dopamine, while still releasing GABA and carrying out all normal synaptic release. (wikipedia.org)
Dividing these nerve cell layers are two neuropils where synaptic contacts occur (Fig. 4). (org.es)
In forming a distal, lateral synaptic network, horizontal cells enrich not only their own physiology but that of presynaptic and postsynaptic partners. (org.es)

There is no retinal tissue overlying the optic nerve head. (medscape.com)
The neuroretina is tightly attached to the underlying retinal pigment only at the margins of the optic nerve and at the ora serrata. (medscape.com)

Here we have succeeded in inducing human iPSC to recapitulate the main steps of retinal development and to form fully laminated 3D retinal tissue by exploiting the intrinsic cues of the system to guide differentiation ( Supplementary Fig. 1 ). (nature.com)

This depolarization was thought of as excitation, and if the excitation was large enough, action potentials, or nerve spikes, were generated to transfer signals down the length of the nerve-cell axon. (org.es)

These are all TH expressing and these amacrine cells modulate light adaption and circadian rhythm. (wikipedia.org)
A third type of light-sensing cell, the photosensitive ganglion cell , is important for entrainment of circadian rhythms and reflexive responses such as the pupillary light reflex . (wikipedia.org)

They also aid in creating functional subunits in the receptive field of ganglion cells. (wikipedia.org)

Horizontal cells have now been studied by numerous investigators using anatomical, biochemical, pharmacological and electrophysiological techniques. (org.es)

Here we report that hiPSC can, in a highly autonomous manner, recapitulate spatiotemporally each of the main steps of retinal development observed in vivo and form three-dimensional retinal cups that contain all major retinal cell types arranged in their proper layers. (nature.com)

Due to the fact that their dendritic arbor size is pretty similar to that of ganglion cells, they could blur the edge of the ganglion cell visual field. (wikipedia.org)
The retinal message concerning the photic input and some preliminary organization of the visual image into several forms of sensation are transmitted to the brain from the spiking discharge pattern of the ganglion cells. (org.es)
Ganglion cells and the visual pathway. (9dok.org)

Induced pluripotent stem cells (iPSCs) hold great potential for the modelling of these diseases or as potential therapeutic agents. (nature.com)

One transcription factor that was found to be selectively expressed in nGnG amacrine cells is Neurod6 Length of dendritic arbors: Based on length, spread of dendritic arbors, amacrine cells can be categorized as narrow field amacrine cells (around 70 micrometers in diameter), medium field amacrine cells (around 170 micrometers in diameter) and wide field amacrine cells (around 350 micrometers in diameter). (wikipedia.org)

Each type of amacrine cell releases one or several neurotransmitters where it connects with other cells. (wikipedia.org)
One type of GABAergic amacrine cell that is fairly well studied is the starburst amacrine cell. (wikipedia.org)
One type of narrow field cells that does this is the starburst amacrine cell. (wikipedia.org)

There are at least 33 different subtypes of amacrine cells based just on their dendrite morphology and stratification. (wikipedia.org)
Different subtypes of amacrine cells project differently in the inner plexiform layer [3] , as shown in the figure to the right depicting different types of narrow-field amacrine cells. (eyewire.org)
These projections arborize differently for different subtypes of amacrine cells. (eyewire.org)

One transcription factor that was found to be selectively expressed in nGnG amacrine cells is Neurod6 Length of dendritic arbors: Based on length, spread of dendritic arbors, amacrine cells can be categorized as narrow field amacrine cells (around 70 micrometers in diameter), medium field amacrine cells (around 170 micrometers in diameter) and wide field amacrine cells (around 350 micrometers in diameter). (wikipedia.org)
Narrow field amacrine cells allow vertical communication among different retinal levels. (wikipedia.org)
These narrow field amacrine cells and their overlap in these subunits can allow certain ganglion cells to detect small amounts of movement of a very small spot in a field of vision. (wikipedia.org)

One type of GABAergic amacrine cell that is fairly well studied is the starburst amacrine cell. (wikipedia.org)
One type of narrow field cells that does this is the starburst amacrine cell. (wikipedia.org)
Starburst amacrine cells exhibit very strange biophysics. (eyewire.org)

GABAergic, glycinergic, or neither: Amacrine cells can be either GABAergic, glycinergic or neither depending on what inhibitory neurotransmitter they express (GABA, glycine, or neither). (wikipedia.org)
Glycinergic amacrine cells aren't as extensively characterized as GABAergic amacrine cells. (wikipedia.org)
All glycinergic amacrine cells though, are marked by the glycine transporter GlyT1. (wikipedia.org)
One very well characterized glycinergic amacrine cell is the AII amacrine cells. (wikipedia.org)
One important function of the AII amacrine cells is that they capture cellular input from rod bipolar cells and redistribute it to cone bipolar cells using the synaptic endings of cone bipolar cells as adaptors Around 15% of amacrine cells are neither GABAergic or glycinergic. (wikipedia.org)
GABAergic/glycinergic) amacrine cells [1] , which make up the majority of amacrine cells, though it is unclear if this holds for all amacrine cells. (eyewire.org)

The short axonal processes of bipolar cells make synaptic contacts in turn on the dendritic processes of ganglion cells in the inner plexiform layer. (nih.gov)
There is no clear distinction between dendrites and axons in the processes of most of the amacrine cells, though they are often referred to as dendrites in general. (eyewire.org)
[4] Further, "amacrine processes are also seen to contact other amacrine processes" in the IPL. (eyewire.org)
A neuron is an electrically excitable cell that processes and transmits information by electrical and chemical signaling. (absoluteastronomy.com)
A transmembrane protein receptor is a protein in the cell membrane that mediates a physiological change in a neuron, most often through the opening of ion channels or changes in the cell signaling processes. (bccampus.ca)

Due to the fact that their dendritic arbor size is pretty similar to that of ganglion cells, they could blur the edge of the ganglion cell visual field. (wikipedia.org)

GABAergic amacrine cells are usually wide field amacrine cells and are found in the ganglion cell layer (GCL) and the inner nuclear layer (INL). (wikipedia.org)
Another subtype of GABAergic amacrine cells are those that are dopaminergic. (wikipedia.org)
Many other divisions of GABAergic amacrine cells have been noted, but those listed above are some of the most extensively researched and discussed. (wikipedia.org)

There is no retinal tissue overlying the optic nerve head. (medscape.com)
The neuroretina is tightly attached to the underlying retinal pigment only at the margins of the optic nerve and at the ora serrata. (medscape.com)
The much larger axons of the ganglion cells form the optic nerve and carry information about retinal stimulation to the rest of the central nervous system . (nih.gov)
There was a suggestion that retinal axons could regenerate after axotomy if the cut optic nerve end was anastomosed to a sciatic nerve graft (Tello, 1907). (org.es)

Most amacrine cells can be classified according to the diameter of their projection arborization: "narrow-field" cells have arbors less than 125 µm in diameter, "medium-field" cell arbors range from 125 to 400 µm in diameter, and "wide-field" cell arbors are larger than 400 µm. (eyewire.org)

Hair cells are the sensory receptors of both the auditory system and the vestibular system in all vertebrates. (absoluteastronomy.com)
This occurs when a stimulus changes the cell membrane potential of a sensory neuron. (bccampus.ca)
The stimulus causes the sensory cell to produce an action potential that is relayed into the central nervous system (CNS), where it is integrated with other sensory information-or sometimes higher cognitive functions-to become a conscious perception of that stimulus. (bccampus.ca)
Sensation is the activation of sensory receptor cells at the level of the stimulus. (bccampus.ca)
Let's start with sensory stimuli that have been registered through receptor cells and the information relayed to the CNS along ascending pathways. (foobrdigital.com)

They also aid in creating functional subunits in the receptive field of ganglion cells. (wikipedia.org)
further up, they collectively form the receptive field of that cell. (absoluteastronomy.com)

The lack of anatomical tracers at that time did not allow us to see whether such regenerating axons were indeed of CNS origin, namely from retinal ganglion cells (RGCs). (org.es)

Each type of amacrine cell releases one or several neurotransmitters where it connects with other cells. (wikipedia.org)

These lateral interactions between receptors, horizontal cells, and bipolar cells in the outer plexiform layer are largely responsible for the visual system's sensitivity to luminance contrast over a wide range of light intensities. (nih.gov)

For example, one such population, AII, 'piggybacks' rod bipolar cells onto the cone bipolar circuitry. (eyewire.org)
It connects rod bipolar cell output with cone bipolar cell input, and from there the signal can travel to the respective ganglion cells . (eyewire.org)

There are about 40 different types of amacrine cells and are classified by the width of their field of connection, which layer(s) of the stratum in the IPL they are in, and by neurotransmitter type. (eyewire.org)
Each type of amacrine cell connects with a particular type of bipolar cell , and generally has a particular type of neurotransmitter. (eyewire.org)

Amacrine cells are interesting biophysically in that they operate using both sodium-mediated action potentials and sodium-independent graded potential changes. (eyewire.org)

Amacrine cells and other retinal interneuron cells are less likely to be near neighbours of the same subtype than would occur by chance, resulting in 'exclusion zones' that separate them. (wikipedia.org)

Receptors are the cells or structures that detect sensations. (bccampus.ca)

Note that on the right edge of the image, the inner cellular layers are laterally displaced. (aao.org)

Amacrine cells send projections from their cell bodies into the inner plexiform layer. (eyewire.org)

Functions of epithelial cells include secretion, selective. (absoluteastronomy.com)

Like horizontal cells, amacrine cells work laterally affecting the output from bipolar cells , however, their tasks are often more specialized. (eyewire.org)

These are all TH expressing and these amacrine cells modulate light adaption and circadian rhythm. (wikipedia.org)

These different lengths lend to different specific functions that the amacrine cells can accomplish. (wikipedia.org)

[2] SAC dendrite-specific direction selectivity is thought to underlie the direction selectivity of on/off direction-selective ganglion cells [2] , but the mechanism by which this direction selectivity is generated in SAC dendrites remains unknown. (eyewire.org)

These cells are present in the INL. (wikipedia.org)
1991) based on the concept that regeneration in the PNS is dependent on the permissive environment provided by Schwann cells present in the nerve tube. (org.es)

A receptor cell is changed directly by a stimulus. (bccampus.ca)

Anatomy15

Organisms11

Chemicals and Drugs18

Analytical, Diagnostic and Therapeutic Techniques and Equipment2

Psychiatry and Psychology1

Phenomena and Processes8

Disciplines and Occupations1

Information Science1

Pigment epithelium8

Neurons10

Ganglion cell2

Retina21

Stratification1

Photoreceptors4

Progenitors1

Synapses2

Subtypes2

Bipolar cells5

Vertebrate2

Vertically1

Synaptic3

Optic2

Tissue1

Nerve cell1

Circadian2

Functional1

Anatomical1

Types1

Visual3

Diseases1

Length1

Type3

Different subtypes of amacrine cells3

Narrow field amacrine cells3

Starburst3

Glycinergic6

Processes5

Dendritic1

GABAergic3

Optic nerve4

Arbors1

Sensory5

Receptive field2

Axons1

Neurotransmitters1

Outer1

Cone bipolar2

Neurotransmitter2

Operate1

Occur1

Receptors1

Cellular1

Bodies1

Epithelial1

Work1

Light1

Functions1

Thought1

Present2

Directly1