Retinal anatomy in some scopelarchid deep-sea fishes

1971 ◽  
Vol 178 (1051) ◽  
pp. 161-184 ◽  
Keyword(s):  
Deep Sea ◽  
Pigment Epithelium ◽  
Horizontal Cell ◽  
Inner Nuclear Layer ◽  
Horizontal Cells ◽  
Diagnostic Feature ◽  
Simple Type ◽  
Focal Distance ◽  
Long Rod ◽  
Retinal Tapetum

An account is given of the retinal structure in two species of Scopelarchus , using optical and electron microscopy. The results confirm previous accounts in most respects but several additional features are described and discussed. Scopelarchus has tubular eyes, their visual axes pointing upwards. The floor of the eyecup is lined by main retina, situated at the focal distance of the lens. The medial wall is lined by accessory retina, which extends onto the anterior and posterior walls and is not at the focal distance. The main retina of Scopelarchus güntheri contains anterior and posterior regions of different structure. Anteriorly there is a uniform population of rods related to an unspecialized pigment epithelium, but in the posterior region the rods are grouped in bundles of about 23. These groups are inserted into pits in a reflecting retinal tapetum formed by the pigment epithelium cells, and are optically as well as spatially isolated from each other. The rods within each group are connected at the sclerad end of the inner segments by patches of tight junction. The neuro-retina has the same structure throughout the main retina; the rod synapses are complex in structure, with about six synaptic ribbons each. There is a major and a minor layer of horizontal cells. The major cells are stellate and their lateral processes have wide areas of contact with those of other cells, forming a perforated sheet of horizontal cell tissue. From the vitread surface of these cells long oblique processes arise. These are embedded in swathes of microtubules and the two elements together form a distinct layer. The inner nuclear layer is subdivided by a layer of lamellae of radial fibre origin. These lamellae, present in other deep-sea fishes, are found throughout the neuro-retina. Scopelarchus sagax has an additional region in the main retina. The anterior third of the retina has long outer segments which are not grouped, and which occur in a very regular array. The long-rod region ends in an abrupt step and gives way to short non-grouped rods resembling those of Scopelarchus güntheri . No significant differences are found in the neuro-retina opposite these two regions. The accessory retina in both species has a grouped structure, but the groups are less regular in size and spatial arrangement than those in the main retina. The rod nuclei are sclerad to the outer limiting zone. There are no inter-receptor contacts between the inner segments, and the synapses are of simple type. The neuro-retina is thin and simple, without horizontal cells or the layer of microtubules. The inner nuclear layer is not subdivided. The ganglion cells are few compared to those in main retina. The retinal tapetum is discussed in relation to those in other fishes, particularly those which also have receptor groups, and conclusions are drawn about their functional implications. The long rods of S. sagax are compared with those of certain other deep-sea fishes, and some implications of their size considered. Attention is drawn to the presence of the long-rod region as a possible diagnostic feature.

scholarly journals Nerve growth factor is expressed by postmitotic avian retinal horizontal cells and supports their survival during development in an autocrine mode of action

Development ◽  
2001 ◽  
Vol 128 (4) ◽  
pp. 471-479
Author(s):  
M. Karlsson ◽  
R. Mayordomo ◽  
L.F. Reichardt ◽  
S. Catsicas ◽  
H. Karten ◽  
...  
Keyword(s):  
Cell Death ◽  
Nerve Growth Factor ◽  
Growth Factor ◽  
Mode Of Action ◽  
Horizontal Cell ◽  
Amacrine Cells ◽  
Inner Nuclear Layer ◽  
Horizontal Cells ◽  
Nerve Growth ◽  
Starting Point

Cell death in the developing retina is regulated, but so far little is known about what factors regulate the cell death. Several neurotrophic factors and receptors, including the neurotrophins and Trk receptors, are expressed during the critical time. We have studied the developing avian retina with respect to the role of nerve growth factor (NGF) in these processes. Our starting point for the work was that NGF and its receptor TrkA are expressed in a partially overlapping pattern in the inner nuclear layer of the developing retina. Our results show that TrkA and NGF-expressing cells are postmitotic. The first NGF-expressing cells were found on the vitreal side of the central region of E5.5-E6 retina. This pattern changed and NGF-expressing cells identified as horizontal cells were later confined to the external inner nuclear layer. We show that these horizontal cells co-express TrkA and NGF, unlike a subpopulation of amacrine cells that only expresses TrkA. In contrast to the horizontal cells, which survive, the majority of the TrkA-expressing amacrine cells die during a period of cell death in the inner nuclear layer. Intraocular injections of NGF protein rescued the dying amacrine cells and injection of antisense oligonucleotides for NGF that block its synthesis, caused death among the TrkA-expressing horizontal cells, which normally would survive. Our results suggest that NGF supports the survival of TrkA expressing avian horizontal cells in an autocrine mode of action in the retina of E10-E12 chicks. The cells co-express TrkA and NGF and the role for NGF is to maintain the TrkA-expressing horizontal cells. The TrkA-expressing amacrine cells are not supported by NGF and subsequently die. In addition to the effect on survival, our results suggest that NGF plays a role in horizontal cell plasticity.

Morphological and functional identifications of catfish retinal neurons. I. Classical morphology

1975 ◽  
Vol 38 (1) ◽  
pp. 53-71 ◽  
Author(s):  
K. Naka ◽  
N. R. Garraway
Keyword(s):  
Ganglion Cells ◽  
Horizontal Cell ◽  
Dendritic Tree ◽  
Amacrine Cells ◽  
Cell Types ◽  
Bipolar Cells ◽  
Inner Nuclear Layer ◽  
Horizontal Cells ◽  
Specific Cell ◽  
Definition Of

The morphology of the catfish horizontal cells is comparable to that in other fish retinas. The external horizontal cells contact cone receptors and are stellate in shape; the intermediate horizontal cells are even more so and contact rod receptors. The internal horizontal cells constitute the most proximal layer of the inner nuclear layer and may possibly be, in reality, extended processes from the other two horizontal cell types. Bipolar cells resemble those in other teleost retinas: the size and shape of their dendritic tree encompass a continuous spectrum ranging from what is known as the small to the large bipolar cells. The accepted definition of amacrine cells is sufficiently vague to justify our originating a more descriptive and less inferential name for the (axonless) neurons in the inner nuclear layer which radiate processes throughout the inner synaptic layer. These starbust and spaghetti cells vary considerably in the character and extent of their dendritic spread, but correlates exist in other vertebrate retinas. Ganglion cells are found not only in the classical ganglion layer but displaced into the inner nuclear layer as well. Several types can be distinguished on the basis of cell geometry and by the properties of their dendritic tree. Not all of the categorization corresponds with previous descriptions; our findings suggest that some reorganization may be necessary in the accepted classification of cells in the proximal areas of the vertebrate retina. A subtle yet remarkable pattern underlies the entire structure of the catfish retina; there exists a definite gradient of size within a particular class of cells, and of configuration among the subclasses of a specific cell type. It remains to be seen if these morphological spectra bear any functional consequences. The fact that the structure of the catfish retina most closely resembles those of other phylogenetically ancient animals, such as the skate and the dogfish shark, testifies to its primitive organization; morphological and functional mechanisms discernible in this simple system may, therefore, be applicable to the retinas of higher ordered vertebrates.

Distribution of F-actin in bipolar and horizontal cells of bass retinas

1990 ◽  
Vol 259 (2) ◽  
pp. C205-C214 ◽  
Author(s):  
D. K. Vaughan ◽  
E. M. Lasater
Keyword(s):  
Pigment Epithelium ◽  
Horizontal Cell ◽  
Horizontal Cells ◽  
Cell Type ◽  
Isolated Cells ◽  
White Bass ◽  
Junctional Conductance ◽  
Normal Coupling ◽  
Plexiform Layers ◽  
Cell Somata

F-actin distribution was studied in bipolar and horizontal interneurons of white bass retina. Cryosections of intact retina and isolated cells in culture were labeled with the F-actin specific probe fluorescent phalloidin. In intact retina, labeling was heaviest in the photoreceptor-pigment epithelium region, outer limiting membrane, horizontal cell somata, and plexiform layers. In isolated bipolar and horizontal cells, labeling patterns specific to each cell type were obtained, as were patterns in distinct categories of neurites extending from cells maintained in culture for several days. Label was especially heavy where contacting horizontal cells apposed and were coupled via extensive gap junctions both in the intact retina and in culture. This observation led to the hypothesis that this F-actin domain might modulate junctional conductance. However, cytochalasin D-induced disruption of the F-actin cytoskeletons of coupled, cultured horizontal cells had no effect on normal coupling or on dopamine-induced uncoupling. The F-actin domain may instead mediate gap junction turnover.

‘Yellow lens’ eyes of a stomiatoid deep-sea fish, Malacosteus niger

1982 ◽  
Vol 215 (1201) ◽  
pp. 481-489 ◽  
Keyword(s):  
Optical Properties ◽  
Deep Sea ◽  
Pigment Epithelium ◽  
Light Organ ◽  
Ecological Significance ◽  
Bright Yellow ◽  
Retinal Tapetum ◽  
Two Peaks ◽  
Sea Fish ◽  
Chemical Evidence

Bright yellow lenses were found in the eyes of the stomiatoid deep-sea fish, Malacosteus niger Ayres. The optical properties of the yellow lens and the retinal specializations in the eyes were examined. Absorption spectra of the yellow lens revealed two peaks at wavelengths 425 and 460 nm. The photoreceptors were all rods and were arranged in two superimposed layers. An astaxanthin-type retinal tapetum was observed in the pigment epithelium. Some chemical evidence is presented showing that the tapetal material is an astaxanthin ester. The ecological significance of the yellow lens is discussed in connection with that of Malacosteus ’ orbital light organ which has a reddish filter.

scholarly journals Lateral feedback from monophasic horizontal cells to cones in carp retina. I. Experiments.

1989 ◽  
Vol 93 (4) ◽  
pp. 681-694 ◽  
Author(s):  
M Kamermans ◽  
B W van Dijk ◽  
H Spekreijse ◽  
R C Zweypfenning
Keyword(s):  
Horizontal Cell ◽  
Horizontal Cells ◽  
Color Coding ◽  
Cell Adaptation ◽  
Test Spot ◽  
Displacement Experiments ◽  
High Stimulus ◽  
Integration Area

The spatial and color coding of the monophasic horizontal cells were studied in light- and dark-adapted retinae. Slit displacement experiments revealed differences in integration area for the different cone inputs of the monophasic horizontal cells. The integration area measured with a 670-nm stimulus was larger than that measured with a 570-nm stimulus. Experiments in which the diameter of the test spot was varied, however, revealed at high stimulus intensities a larger summation area for 520-nm stimuli than for 670-nm stimuli. The reverse was found for low stimulus intensities. To investigate whether these differences were due to interaction between the various cone inputs to the monophasic horizontal cell, adaptation experiments were performed. It was found that the various cone inputs were not independent. Finally, some mechanisms for the spatial and color coding will be discussed.

Receptive field of the retinal bipolar cell: a pharmacological study in the tiger salamander

1996 ◽  
Vol 76 (3) ◽  
pp. 2005-2019 ◽  
Author(s):  
W. A. Hare ◽  
W. G. Owen
Keyword(s):  
Receptive Field ◽  
Gaba Receptors ◽  
Bipolar Cell ◽  
Horizontal Cell ◽  
Pharmacological Study ◽  
Bipolar Cells ◽  
Horizontal Cells ◽  
Gaba Uptake ◽  
Gamma Aminobutyric Acid ◽  
Gabaergic Synapse

1. It is widely believed that signals contributing to the receptive field surrounds of retinal bipolar cells pass from horizontal cells to bipolar cells via GABAergic synapses. To test this notion, we applied gamma-aminobutyric acid (GABA) agonists and antagonists to isolated, perfused retinas of the salamander Ambystoma tigrinum while recording intracellularly from bipolar cells, horizontal cells, and photoreceptors. 2. As we previously reported, administration of the GABA analogue D-aminovaleric acid in concert with picrotoxin did not block horizontal cell responses or the center responses of bipolar cells but blocked the surround responses of both on-center and off-center bipolar cells. 3. Surround responses were not blocked by the GABA, antagonists picrotoxin or bicuculline, the GABAB agonist baclofen or the GABAB antagonist phaclofen, and the GABAC antagonists picrotoxin or cis-4-aminocrotonic acid. Combinations of these drugs were similarly ineffective. 4. GABA itself activated a powerful GABA uptake mechanism in horizontal cells for which nipecotic acid is a competitive agonist. It also activated, both in horizontal cells and bipolar cells, large GABAA conductances that shunted light responses but that could be blocked by picrotoxin or bicuculline. 5. GABA, administered together with picrotoxin to block the shunting effect of GABAA activation, did not eliminate bipolar cell surround responses at concentrations sufficient to saturate the known types of GABA receptors. 6. Surround responses were not blocked by glycine or its antagonist strychnine, or by combinations of drugs designed to eliminate GABAergic and glycinergic pathways simultaneously. 7. Although we cannot fully discount the involvement of a novel GABAergic synapse, the simplest explanation of our findings is that the primary pathway mediating the bipolar cell's surround is neither GABAergic nor glycinergic.

Nitric oxide and cGMP modulate retinal glutamate receptors

1996 ◽  
Vol 76 (4) ◽  
pp. 2307-2315 ◽  
Author(s):  
D. G. McMahon ◽  
L. V. Ponomareva
Keyword(s):  
Nitric Oxide ◽  
Glutamate Receptors ◽  
Horizontal Cell ◽  
Synaptic Function ◽  
Horizontal Cells ◽  
Glutamate Excitotoxicity ◽  
No Donors ◽  
Receptor Modulation ◽  
Cell Recording ◽  
Endogenous Nitric Oxide

1. In the retina, as in other regions of the vertebrate central nervous system, glutamate receptors mediate excitatory chemical synaptic transmission and are a critical site for the regulation of cellular communication. In this study, retinal horizontal cells from the hybrid less were dissociated in cell culture, voltage clamped by the whole cell recording technique, and the currents evoked by application of excitatory amino acids recorded. 2. Responses to glutamate and its agonist kainate were reduced by approximately 50% in the presence of the nitric oxide (NO) donors sodium nitroprusside and S-nitroso-N-acetylpenicillamine. The effect of these compounds was blocked by the NO scavenger hemoglobin. 3. This effect of NO donors on kainate currents could be mimicked by the application of a membrane permeable guanosine 3',5'-cyclic monophosphate (cGMP) analogue, 8-Br-cGMP. The NO effect was also blocked by application of the guanylate cyclase inhibitor LY-83583, and by a protein kinase G inhibitor peptide. 4. In H1-type horizontal cells, stimulation of endogenous nitric oxide synthase with L-arginine reduced kainate responses, whereas application of D-arginine had no effect. 5. This receptor modulation mechanism may act in concert with other pre- and postsynaptic mechanisms to modify horizontal cell synaptic function according to the adaptational state of the retina and also may protect horizontal cells from glutamate excitotoxicity.

3H-adenosine uptake selectively labels rod horizontal cells in goldfish retina

1997 ◽  
Vol 14 (2) ◽  
pp. 207-212 ◽  
Author(s):  
Keith M. Studholme ◽  
Stephen Yazulla
Keyword(s):  
Staining Pattern ◽  
Outer Nuclear Layer ◽  
Horizontal Cell ◽  
Horizontal Cells ◽  
The Other ◽  
Axon Terminals ◽  
Adenosine Uptake ◽  
Double Label ◽  
Injection Methods ◽  
Goldfish Retina

AbstractThere are four types of horizontal cell in the goldfish retina, three cone- and one rod-type. The neurotransmitter of only one type, the H1 (cone) horizontal cell, has been identified as GABA. 3H-adenosine uptake was examined as a possible marker for the other classes of horizontal cell. Isolated goldfish retinae were incubated in 3H-adenosine (10–40 μCi) in HEPES-buffered saline for 30 min, then fixed, embedded in plastic, and processed for light-microscopic autoradiography (ARG). For double-label immuno/ARG studies, l-μm-thick sections were processed for GABA postembed immunocytochemistry, then for ARG. 3H-adenosine uptake was localized to cone photoreceptors, presumed precursor cells in the proximal outer nuclear layer, and to a single, continuous row of horizontal cell bodies in the inner nuclear layer. No uptake was localized to the region of horizontal cell axon terminals. 3H-adenosine uptake did not colocalize with GABA-IR in H1 horizontal cells, but it did colocalize with adenosine deaminase immunoreactivity. It is concluded that 3H-adenosine uptake selectively labels rod horizontal cells in the goldfish retina based on position and staining pattern, which are similar to rod horizontal cells stained by Golgi or HRP injection methods. The use of 3H-adenosine uptake may provide a useful tool to study other properties of rod horizontal cells (i.e. development) as well as provide clues as to the transmitter used by these interneurons.

Dual effect of glycine on horizontal cells of the tiger salamander retina

1991 ◽  
Vol 66 (6) ◽  
pp. 1993-2001 ◽  
Author(s):  
S. Borges ◽  
M. Wilson
Keyword(s):  
Opposite Effect ◽  
Horizontal Cell ◽  
Light Response ◽  
Membrane Resistance ◽  
Horizontal Cells ◽  
Field Size ◽  
Dual Effect ◽  
Light Responses ◽  
Low Concentrations ◽  
High Concentrations

1. The effects of glycine on horizontal cells have been examined by microelectrode recording from superfused retinas isolated from the salamander. 2. Low concentrations of glycine (less than 50 microM) hyperpolarized horizontal cells and increased the magnitude of their light responses. Millimolar concentrations produced the opposite effect of depolarizing these cells and reducing their light response amplitudes. 3. In the presence of Co2+ and Mg2+ at concentrations sufficient to suppress the light response, millimolar glycine still exerted a depolarizing effect on horizontal cells, implying that this effect was largely a direct one on horizontal cell membranes. 4. Although both the rod and the cone contributions to horizontal cell light responses were reduced by millimolar glycine, rod input was reduced more, suggesting that millimolar glycine may also exert a presynaptic effect. 5. Strychnine (10 microns) antagonized the effects of millimolar glycine and, in the absence of exogenously applied glycine, caused horizontal cells to hyperpolarize and their light responses to increase in amplitude. This result implies that, in darkness, glycine is tonically released onto horizontal cells and maintains them in a state of partial depolarization. 6. The low-concentration effect of glycine was accompanied by an increased membrane resistance and receptive field size but no change in the balance of rod and cone input. 7. Low concentrations of glycine were often seen to cause a speeding of light responses, whereas high concentrations sometimes caused a slowing of response kinetics. Response kinetics were found to correlate with horizontal cell dark membrane potential so that, positive to -30 mV, depolarization slowed responses whereas kinetics at more negative values were largely independent of voltage.

Bifurcation analysis of nonlinear retinal horizontal cell models. II. Network properties

1990 ◽  
Vol 64 (1) ◽  
pp. 248-261 ◽  
Author(s):  
R. L. Winslow ◽  
S. Ma
Keyword(s):  
Horizontal Cell ◽  
Membrane Currents ◽  
Horizontal Cells ◽  
Synaptic Conductance ◽  
Cell Models ◽  
Voltage Dependent ◽  
Full Complement ◽  
Network Properties ◽  
Light Stimuli ◽  
Coupling Conductance

1. We have previously presented a model of horizontal-cell soma isolated from fish retina. The model consists of a synaptic conductance representing input from photoreceptors in parallel with voltage-dependent membrane currents. Membrane-current models are based on I-V curves measured in isolated fish horizontal cells. Bifurcation theory was used to analyze model properties. The major findings of this study were 1) the inward Ca2+ current must be inactivated to account for horizontal-cell resting potentials and hyperpolarizing responses to light stimuli in a background of dark, and 2) the synaptic conductance controls the bifurcation structure of the model, with bistable behavior occurring at small and monostable behavior occurring at larger values of the synaptic conductance. The synaptic conductance at the point of transition from bistable to monostable behavior corresponds to the activation of as few as 100 synaptic channels. Thus tonic synaptic input from photoreceptors and inactivation of the inward Ca2+ current act to “linearize” responses of isolated horizontal-cell models. 2. The model described in this paper extends these analyses to large networks of horizontal cells in which each cell is coupled resistively to its nearest neighbors and is modeled with the use of the full complement of nonlinear membrane currents. Network responses to arbitrary patterns of conductance change (simulating inputs from photoreceptors), current-, or voltage-clamp stimuli are computed using the Newton iteration. The Newton descent direction is computed using either conjugate gradient (CG) or preconditioned CG algorithms. 3. An analysis of network stability properties is performed. Network I-V curves are computed by voltage-clamping the center node and computing the current required to maintain the clamp voltage. Computations are performed on networks of model cells in which the Ca2+ current is fully activated and the synaptic conductance is zero, thus making each cell as nonlinear as possible. Coupling conductance values slightly greater than 100 pS provide a current shunt sufficient to prevent the generation of Ca2+ action potentials in the network. This coupling conductance corresponds to the conductance of as few as two gap-junction channels and is more than two orders of magnitude less than the coupling known to exist between pairs of cultured horizontal cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Sign in / Sign up

Export Citation Format

Share Document