The photoresponses of structurally identified amacrine cells in the turtle retina

1982 ◽  
Vol 214 (1196) ◽  
pp. 403-415 ◽  
Keyword(s):  
Time Course ◽  
Amacrine Cell ◽  
Ganglion Cells ◽  
Plexiform Layer ◽  
Amacrine Cells ◽  
Homogeneous Distribution ◽  
Inner Plexiform Layer ◽  
Intracellular Recordings ◽  
Cell Processes ◽  
Layer I

Intracellular recordings were obtained from amacrine cells afterwards identified morphologically by horseradish peroxidase injection. There is a correlation between the time course of the photoresponses and the distribution of the cell processes across the inner plexiform layer (i. p. l.). Cells producing the shortest duration, transient ‘on‒off’ photoresponses branched in a single, narrow stratum of the i. p. l. (3‒7 μm across). Transient photoresponses with a longer time course were recorded from cells branching in a thicker stratum of i. p. l. (up to 20 μm), or from bistratified cells. Amacrine cells producing sustained centre-on or centre-off photoresponses were radially diffused across the whole i. p. l.; therefore this type of photoresponse need not be associated with a specific cellular stratification within the i. p. l. It is concluded that the two main functional types of amacrine cell, i. e. transient on‒off and sustained centre-on and centre-off, are subject to different structural organization of inputs than are the homologous physiological types of ganglion cells in this species, in the cat and in the carp. In a summary diagram the observed characteristics of the photoresponses are tentatively explained in term s of a non-homogeneous distribution of bipolar synaptic inputs along amacrine cell processes.

Disruption of transient photoreceptor targeting within the inner plexiform layer following early ablation of cholinergic amacrine cells in the ferret

2001 ◽  
Vol 18 (5) ◽  
pp. 741-751 ◽  
Author(s):  
P.T. JOHNSON ◽  
M.A. RAVEN ◽  
B.E. REESE
Keyword(s):  
Retinal Ganglion Cells ◽  
Amacrine Cell ◽  
Ganglion Cells ◽  
Plexiform Layer ◽  
Amacrine Cells ◽  
Inner Plexiform Layer ◽  
Retinal Ganglion ◽  
Subcutaneous Injections ◽  
Cell Processes ◽  
Cholinergic Amacrine Cells

Photoreceptors in the ferret's retina have been shown to project transiently to the inner plexiform layer (IPL) prior to their differentiation of an outer segment. On postnatal day 15 (P-15), when this projection achieves maximal density, the photoreceptors projecting into the IPL extend primarily to one of two depths, coincident with the processes of cholinergic amacrine cells. The present study has used an excitotoxic approach employing subcutaneous injections of l-glutamate to ablate these cholinergic amacrine cells on P-7, in order to see whether their elimination alters this targeting of photoreceptor terminals within the IPL. The near-complete elimination of cholinergic amacrine cells at P-15 was confirmed, although the population of retinal ganglion cells was also affected, being depleted by roughly 50%. The rod opsin-immunopositive terminals in such treated ferrets no longer showed a stratified distribution, being found throughout the depth of the IPL, as well as extending into the ganglion cell layer. This effect should not be due to the partial loss of retinal ganglion cells, however, since optic nerve transection at P-2, which eliminates the ganglion cells entirely while leaving the cholinergic amacrine cell population intact, was shown not to affect the stratification pattern of the photoreceptors within the IPL. These results strongly suggest that the targeting of the photoreceptor terminals to discrete strata within the IPL is dependent upon the cholinergic amacrine cell processes.

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

2002 ◽  
Vol 19 (3) ◽  
pp. 299-305 ◽  
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.

Synaptic connections involving immunoreactive glycine receptors in the turtle retina

1993 ◽  
Vol 10 (5) ◽  
pp. 907-914 ◽  
Author(s):  
Charles L. Zucker ◽  
Berndt Ehinger
Keyword(s):  
Amacrine Cell ◽  
Ganglion Cells ◽  
Glycine Receptor ◽  
Plexiform Layer ◽  
Photoreceptor Cells ◽  
Bimodal Distribution ◽  
Inner Nuclear Layer ◽  
Inner Plexiform Layer ◽  
Glycine Receptors ◽  
Cell Processes

AbstractThe distribution of glycine receptors in the turtle retina was studied with the aid of a monoclonal antibody that detects the 93-kD protein associated with the strychnine-sensitive glycine receptor. Light microscopically, receptors were found in the inner plexiform layer and, more sparsely, in the innermost parts of the inner nuclear layer. No receptors were seen to be associated with photoreceptor cells, horizontal cells, or any other structures in the distal inner nuclear layer or outer plexiform layer. Ultrastructurally, glycine receptors were found on the inner face of postsynaptic membranes of processes from amacrine and presumed ganglion cells and always involved amacrine cell processes as the presynaptic element. Such glycine receptor immunoreactive synapses onto amacrine cell processes were distributed throughout the inner plexiform layer with a peak density near the middle. On the other hand, output synapses onto ganglion cell processes displaying immunoreactive glycine receptor sites showed a bimodal distribution in the inner plexiform layer. Glycine receptor immunoreactivity was not detected on bipolar cells, but presumed glycine-utilizing processes (i.e. those presynaptic to immunoreactive glycine receptors) were occasionally found to be postsynaptic in bipolar cell dyads. The majority of the synaptic input to the presumed glycine-utilizing amacrine cell processes was from other amacrine processes, some of which were themselves glycine utilizing. The observations suggest that glycinergic synapses in the turtle retina are, to a large extent, engaged in processing interamacrine signals.

scholarly journals Heterocellular coupling between amacrine cell and ganglion cells

2018 ◽  
Author(s):  
Robert E. Marc ◽  
Crystal Sigulinsky ◽  
Rebecca L. Pfeiffer ◽  
Daniel Emrich ◽  
James R. Anderson ◽  
...  
Keyword(s):  
Gap Junctions ◽  
Ganglion Cell ◽  
Bipolar Cell ◽  
Amacrine Cell ◽  
Ganglion Cells ◽  
Plexiform Layer ◽  
Amacrine Cells ◽  
Bipolar Cells ◽  
Inner Plexiform Layer ◽  
Tem Analysis

AbstractAll superclasses of retinal neurons display some form of electrical coupling including the key neurons of the inner plexiform layer: bipolar cells (BCs), amacrine or axonal cells (ACs) and ganglion cells (GCs). However, coupling varies extensively by class. For example, mammalian rod bipolar cells form no gap junctions at all, while all cone bipolar cells form class-specific coupling arrays, many of them homocellular in-superclass arrays. Ganglion cells are unique in that classes with coupling predominantly form heterocellular cross-class arrays of ganglion cell::amacrine cell (GC::AC) coupling in the mammalian retina. Ganglion cells are the least frequent superclass in the inner plexiform layer and GC::AC gap junctions are sparsely arrayed amidst massive cohorts of AC::AC, bipolar cell BC::BC, and AC::BC gap junctions. Many of these gap junctions and most ganglion cell gap junctions are suboptical, complicating analysis of specific ganglion cells. High resolution 2 nm TEM analysis of rabbit retinal connectome RC1 allows quantitative GC::AC coupling maps of identified ganglion cells. Ganglion cells classes apparently avoid direct cross-class homocellular coupling altogether even though they have opportunities via direct membrane touches, while transient OFF alpha ganglion cells and transient ON directionally selective (DS) ganglion cells are strongly coupled to distinct amacrine / axonal cell cohorts.A key feature of coupled ganglion cells is intercellular metabolite flux. Most GC::AC coupling involves GABAergic cells (γ+ amacrine cells), which results in significant GABA flux into ganglion cells. Surveying GABA coupling signatures in the ganglion cell layer across species suggests that the majority of vertebrate retinas engage in GC::AC coupling.Multi-hop synaptic queries of the entire RC1 connectome clearly profiles the coupled amacrine and axonal cells. Photic drive polarities and source bipolar cell class selec-tivities are tightly matched across coupled cells. OFF alpha ganglion cells are coupled to OFF γ+ amacrine cells and transient ON DS ganglion cells are coupled to ON γ+ amacrine cells including a large interstitial axonal cell (IAC). Synaptic tabulations show close matches between the classes of bipolar cells sampled by the coupled amacrine and ganglion cells. Further, both ON and OFF coupling ganglion networks show a common theme: synaptic asymmetry whereby the coupled γ+ neurons are also presynaptic to ganglion cell dendrites from different classes of ganglion cells outside the coupled set. In effect, these heterocellular coupling patterns enable an excited ganglion cell to directly inhibit nearby ganglion cells of different classes. Similarly, coupled γ+ amacrine cells engaged in feedback networks can leverage the additional gain of bipolar cell synapses in shaping the signaling of a spectrum of downstream targets based on their own selective coupling with ganglion cells.

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

1995 ◽  
Vol 12 (5) ◽  
pp. 919-927 ◽  
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.

Glycine in the lizard retina: Comparison to the GABA system

1993 ◽  
Vol 10 (4) ◽  
pp. 693-702 ◽  
Author(s):  
David M. Sherry ◽  
Alex Micich ◽  
Stephen Yazulla
Keyword(s):  
Amacrine Cell ◽  
Ganglion Cells ◽  
Plexiform Layer ◽  
Amacrine Cells ◽  
Inner Plexiform Layer ◽  
Gamma Aminobutyric Acid ◽  
Serial Sections ◽  
Cell Type ◽  
Neuronal Populations ◽  
Retinal Processing

AbstractNeurons likely to utilize glycine (GLY) as a neurotransmitter were identified immunocytochemically in the “all-cone” lizard retina and the basic anatomical organization of the retinal GLY and gamma-aminobutyric acid (GABA) systems was compared. Four types of GLY-immunoreactive (GLY-IR) neurons were identified. Most GLY-IR cells were amacrine cells, which comprised at least two types. GLY-IR interplexiform cells and ganglion cells also were identified. The first GLY-IR amacrine cell type was characterized by a small pyriform soma, located distal to the border of the inner plexiform layer (IPL), and fine dendrites. Most GLY-IR amacrine cells were of this type and several subtypes may exist within this group. The second amacrine cell type was characterized by a large, distally located soma and a large descending process. This amacrine cell type showed colocalization of GLY-IR and GABA-IR and comprised about 4% of the total GLY-IR amacrine cell population.Comparison of GLY-IR and GABA-IR on serial sections showed that GLY and GABA were present in largely separate neuronal populations. Generally, GLY-IR amacrine cells were smaller, more distally located in the inner nuclear layer and had finer dendrites than GABA-IR amacrine cells. Distribution of GLY-IR and GABA-IR in the outer plexiform layer and the inner plexiform layer differed considerably.Based on the segregated distribution of GLY-IR and GABA-IR in the synaptic layers of the lizard retina, GLY and GABA may have fundamentally different roles in retinal processing.

Synaptic microcircuitry of bipolar and amacrine cells with serotonin-like immunoreactivity in the retina of the turtle, Pseudemys scripta elegans

1993 ◽  
Vol 10 (3) ◽  
pp. 455-471 ◽  
Author(s):  
Lawrence B. Hurd ◽  
William D. Eldred
Keyword(s):  
Bipolar Cell ◽  
Amacrine Cell ◽  
Plexiform Layer ◽  
Amacrine Cells ◽  
Bipolar Cells ◽  
Outer Plexiform Layer ◽  
Inner Plexiform Layer ◽  
Synaptic Contacts ◽  
Synaptic Inputs ◽  
Cell Processes

AbstractAlthough serotonin is thought to be a neurotransmitter in a number of retinal systems, much of the precise synaptic connectivity of serotonergic neurons is unknown. To address this issue, we used an antiserum directed against serotonin to label serotonergic bipolar and amacrine cells in the turtle retina. Light-microscopic analysis of labeled amacrine and bipolar cells indicated that both had bistratified dendritic arborizations primarily in stratum 1 and in strata 4/5 of the inner plexiform layer.Ultrastructural analysis of the neurocircuitry of these cells indicated that the processes of labeled bipolar cells in the outer plexiform layer made basal junction contacts with photoreceptor terminals. Only in rare instances did labeled bipolar cells processes invaginate near photoreceptor ribbon synapses. Processes of labeled bipolar cells received both conventional and small ribbon synaptic contacts in the outer plexiform layer. Bipolar cell processes in stratum 1 of the inner plexiform layer synapsed onto either amacrine/amacrine or amacrine/ganglion cell dyads, and made rare ribbon synaptic contacts onto labeled amacrine cell processes. Synaptic inputs to serotonergic bipolar cells in stratum 1 were from unlabeled bipolar and amacrine cells. Bipolar cell contacts in strata 4/5 were similar to those in stratum 1, but were fewer in number and no bipolar cell inputs were seen.Labeled amacrine cell output in both strata was onto other unlabeled amacrine cells and ganglion cells; but synaptic outputs to unlabeled bipolar cells were only seen in strata 4/5. In both strata 1 and 4/5, synaptic inputs to labeled amacrine cells were from both unlabeled amacrine cells and labeled bipolar cells. The serotonergic amacrine cells had many more synaptic interactions in stratum 1 than in strata 4/5 which supports the role of serotonergic bipolar cells in the OFF pathway of retinal processing. Interactions between serotonergic bipolar and amacrine cells may play an important role in visual processing.

A coupled network for parasol but not midget ganglion cells in the primate retina

1992 ◽  
Vol 9 (3-4) ◽  
pp. 279-290 ◽  
Author(s):  
Dennis M. Dacey ◽  
Sarah Brace
Keyword(s):  
Nearest Neighbor ◽  
Ganglion Cells ◽  
Plexiform Layer ◽  
Amacrine Cells ◽  
Cell Types ◽  
Distinct Pattern ◽  
Field Size ◽  
Inner Plexiform Layer ◽  
Dendritic Field

AbstractIntracellular injections of Neurobiotin were used to determine whether the major ganglion cell classes of the macaque monkey retina, the magnocellular-projecting parasol, and the parvocellular-projecting midget cells showed evidence of cellular coupling similar to that recently described for cat retinal ganglion cells. Ganglion cells were labeled with the fluorescent dye acridine orange in an in vitro, isolated retina preparation and were selectively targeted for intracellular injection under direct microscopic control. The macaque midget cells, like the beta cells of the cat's retina, showed no evidence of tracer coupling when injected with Neurobiotin. By contrast, Neurobiotin-filled parasol cells, like cat alpha cells, showed a distinct pattern of tracer coupling to each other (homotypic coupling) and to amacrine cells (heterotypic coupling).In instances of homotypic coupling, the injected parasol cell was surrounded by a regular array of 3–6 neighboring parasol cells. The somata and proximal dendrites of these tracer-coupled cells were lightly labeled and appeared to costratify with the injected cell. Analysis of the nearest-neighbor distances for the parasol cell clusters showed that dendritic-field overlap remained constant as dendritic-field size increased from 100–400 μm in diameter.At least two amacrine cell types showed tracer coupling to parasol cells. One amacrine type had a small soma and thin, sparsely branching dendrites that extended for 1–2 mm in the inner plexiform layer. A second amacrine type had a relatively large soma, thick main dendrites, and distinct, axon-like processes that extended for at least 2–3 mm in the inner plexiform layer. The main dendrites of the large amacrine cells were closely apposed to the dendrites of parasol cells and may be the site of Neurobiotin transfer between the two cell types. We suggest that the tracer coupling between neighboring parasol cells takes place indirectly via the dendrites of the large amacrine cells and provides a mechanism, absent in midget cells, for increasing parasol cell receptive-field size and luminance contrast sensitivity.

Development of cholinergic amacrine cell stratification in the ferret retina and the effects of early excitotoxic ablation

2001 ◽  
Vol 18 (4) ◽  
pp. 559-570 ◽  
Author(s):  
B.E. REESE ◽  
M.A. RAVEN ◽  
K.A. GIANNOTTI ◽  
P.T. JOHNSON
Keyword(s):  
Ganglion Cell ◽  
Ganglion Cells ◽  
Plexiform Layer ◽  
Amacrine Cells ◽  
Cell Types ◽  
Retinal Cell ◽  
Inner Plexiform Layer ◽  
Retinal Ganglion ◽  
Outer Border ◽  
Cholinergic Amacrine Cells

The present study has examined the emergence of cholinergic stratification within the developing inner plexiform layer (IPL), and the effect of ablating the cholinergic amacrine cells on the formation of other stratifications within the IPL. The population of cholinergic amacrine cells in the ferret's retina was identified as early as the day of birth, but their processes did not form discrete strata until the end of the first postnatal week. As development proceeded over the next five postnatal weeks, so the positioning of the cholinergic strata shifted within the IPL toward the outer border, indicative of the greater ingrowth and elaboration of processes within the innermost parts of the IPL. To examine whether these cholinergic strata play an instructive role upon the development of other stratifications which form within the IPL, one-week-old ferrets were treated with l-glutamate in an attempt to ablate the population of cholinergic amacrine cells. Such treatment was shown to be successful, eliminating all of the cholinergic amacrine cells as well as the alpha retinal ganglion cells in the central retina. The remaining ganglion cell classes as well as a few other retinal cell types were partially reduced, while other cell types were not affected, and neither retinal histology nor areal growth was compromised in these ferrets. Despite this early loss of the cholinergic amacrine cells, which are eliminated within 24 h, other stratifications within the IPL formed normally, as they do following early elimination of the entire ganglion cell population. While these cholinergic amacrine cells are present well before other cell types have differentiated, apparently neither they, nor the ganglion cells, play a role in determining the depth of stratification for other retinal cell types.

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