Two-Photon Imaging of Nonlinear Glutamate Release Dynamics at Bipolar Cell Synapses in the Mouse Retina

Journal of Neuroscience, Journal Year: 2013, Volume and Issue: 33(27), P. 10972 - 10985

Published: July 3, 2013

Alpha/Y-type retinal ganglion cells encode visual information with a receptive field composed of nonlinear subunits. This subunit structure enhances sensitivity to patterns high spatial frequencies. The Y-cell's subunits are the presynaptic bipolar cells, but mechanism for nonlinearity remains incompletely understood. We investigated synaptic basis by combining whole-cell recording mouse Y-type two-photon fluorescence imaging glutamate sensor (iGluSnFR) expressed on their dendrites and throughout inner plexiform layer. A control experiment designed assess iGluSnFR's dynamic range showed that responses from Y-cell increased proportionally simultaneously recorded excitatory current. Spatial resolution was sufficient readily resolve independent release at intermingled ON OFF terminals. iGluSnFR strong surround inhibition, reflecting properties sites. Responses located origin cell output, after stage integration. underlying differed between pathways: synapses transient rectification, whereas relatively sustained weak rectification. At synapses, combination fast onset slower offset explained response postsynaptic cell. Imaging layer, we found transient, rectified central-most levels, increasingly near borders. By visualizing in real time, provides powerful tool characterizing intact neural circuits.

Language: Английский

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Genetic Dissection of Retinal Inputs to Brainstem Nuclei Controlling Image Stabilization

Journal of Neuroscience, Journal Year: 2013, Volume and Issue: 33(45), P. 17797 - 17813

Published: Nov. 6, 2013

When the head rotates, image of visual world slips across retina. A dedicated set retinal ganglion cells (RGCs) and brainstem nuclei termed “accessory optic system” (AOS) generate slip-compensating eye movements that stabilize images on retina improve performance. Which types RGCs project to each various AOS remain unresolved. Here we report a new transgenic mouse line, Hoxd10–GFP, in which projecting all are fluorescently labeled. Electrophysiological recordings Hoxd10–GFP revealed they include three subtypes On direction-selective (On–DSGCs), responding upward, downward, or forward motion. also one subtype On–Off DSGCs tuned for Retrograde circuit mapping with modified rabies viruses On–DSGCs centers involved both horizontal vertical slip compensation. In contrast, labeled mice projected controlling but not stabilization. Moreover, appear physiologically molecularly distinct from previously genetically identified DSGCs. These data begin clarify cell circuits underlying stabilization during self-motion, support an unexpected diversity DSGC subtypes.

Language: Английский

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Ambient Illumination Toggles a Neuronal Circuit Switch in the Retina and Visual Perception at Cone Threshold

Neuron, Journal Year: 2013, Volume and Issue: 78(2), P. 325 - 338

Published: March 28, 2013

Language: Английский

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Photoresponse diversity among the five types of intrinsically photosensitive retinal ganglion cells

The Journal of Physiology, Journal Year: 2014, Volume and Issue: 592(7), P. 1619 - 1636

Published: Jan. 7, 2014

Intrinsically photosensitive retinal ganglion cells (ipRGCs) mediate non-image-forming visual responses, including pupillary constriction, circadian photoentrainment and suppression of pineal melatonin secretion. Five morphological types ipRGCs, M1-M5, have been identified in mice. In order to understand their functions better, we studied the photoresponses all five cell types, by whole-cell recording from fluorescently labelled ipRGCs visualized using multiphoton microscopy. All ipRGC generated melanopsin-based ('intrinsic') as well synaptically driven ('extrinsic') light responses. The intrinsic M1 were lower threshold, higher amplitude faster than those M2-M5. peak amplitudes extrinsic responses differed among types; however, had comparable thresholds, kinetics waveforms, received rod input. While exhibited inhibitory amacrine-cell excitatory bipolar-cell inputs 'on' channel, M3 additional 'off'-channel inhibition, possibly through 'off'-sublamina dendrites. M2-M5 centre-surround-organized receptive fields, implicating a capacity detect spatial contrast. contrast, fields lacked surround antagonism, which might be caused input nullifying responded robustly wide range motion speeds, M1-M4 appeared tuned different suggesting that they analyse speed motion. Retrograde labelling revealed project superior colliculus, contrast information signalled these could used this sensorimotor area novel objects field.

Language: Английский

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The Post-Illumination Pupil Response (PIPR)

Investigative Ophthalmology & Visual Science, Journal Year: 2015, Volume and Issue: 56(6), P. 3838 - 3838

Published: June 11, 2015

Purpose.: The post-illumination pupil response (PIPR) has been quantified using four metrics, but the spectral sensitivity of only one is known; here we determine other three. To optimize human PIPR measurement, protocol producing largest PIPR, duration and metric(s) with lowest coefficient variation. Methods.: consensual light reflex (PLR) was measured a Maxwellian view pupillometer. Experiment 1: Spectral metrics (plateau, 6 seconds, area under curve early late recovery) determined from criterion to 1-second pulse fitted vitamin A1 nomogram (λmax = 482 nm). 2: PLR as function three stimulus durations (1 second, 10 30 seconds), five irradiances spanning low high melanopsin excitation levels (retinal irradiance: 9.8–14.8 log quanta.cm−2.s−1), two wavelengths, (465 nm) (637 excitation. Intra- interindividual coefficients variation (CV) were calculated. Results.: (opn4) photopigment adequately describes all metrics. amplitude short-wavelength pulses (≥12.8 quanta.cm−2.s−1). plateau 6-second showed least intra- CV (≤0.2). maximum sustained 83.0 ± 48.0 seconds (mean SD) for 180.1 106.2 30-second nm; 14.8 Conclusions.: All current provide direct measure intrinsic photoresponse. progressive changes in disease, recommend that be short-duration (e.g., ≤1 second) analyzed and/or Our data baseline selection interstimulus intervals between consecutive testing sequences.

Language: Английский

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Melanopsin expressing human retinal ganglion cells: Subtypes, distribution, and intraretinal connectivity

The Journal of Comparative Neurology, Journal Year: 2017, Volume and Issue: 525(8), P. 1934 - 1961

Published: Feb. 4, 2017

Intrinsically photosensitive retinal ganglion cells (ipRGCs) expressing the photopigment melanopsin belong to a heterogenic population of RGCs which regulate circadian clock, masking behavior, melatonin suppression, pupillary light reflex, and sleep/wake cycles. The different functions seem be associated subtypes cells. In rodents, subtype classification has function. primate human retina such so far, not been applied. present study using antibodies against N- C-terminal parts melanopsin, confocal microscopy 3D reconstruction immunoreactive (-ir) RGCs, we applied criteria used in mouse on melanopsin-ir RGCs. We identified M1, displaced M2, M4 found two other were named "gigantic M1 (GM1)" (GDM1)." Few M3 no M5 labeled. Total cell counts from one male female revealed that contains 7283 ± 237 (0.63-0.75% total number RGCs). unevenly distributed. Most significant was highest density nasal retina. input AII amacrine directly rod bipolar via ribbon synapses innermost ON layer inner plexiform (IPL) dopaminergic GABAergic processes outermost OFF IPL. characterizes most likely are involved functions.

Language: Английский

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Contributions of Retinal Ganglion Cells to Subcortical Visual Processing and Behaviors

Annual Review of Vision Science, Journal Year: 2015, Volume and Issue: 1(1), P. 291 - 328

Published: Nov. 18, 2015

Every aspect of visual perception and behavior is built from the neural activity retinal ganglion cells (RGCs), output neurons eye. Here, we review progress toward understanding many types RGCs that communicate signals to brain, along with subcortical brain regions use those build respond representations outside world. We emphasize recent in mouse genetics, viral circuit tracing, behavioral psychophysics define map various their associated networks. also address questions about homology RGC mice other species including nonhuman primates humans. Finally, propose a framework for typology highlighting relationship between type-specific circuitry processing stations support give rise sight.

Language: Английский

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The M6 cell: A small‐field bistratified photosensitive retinal ganglion cell

The Journal of Comparative Neurology, Journal Year: 2018, Volume and Issue: 527(1), P. 297 - 311

Published: Oct. 12, 2018

Abstract We have identified a novel, sixth type of intrinsically photosensitive retinal ganglion cell (ipRGC) in the mouse—the M6 cell. Its spiny, highly branched dendritic arbor is bistratified, with dendrites restricted to inner and outer margins plexiform layer, co‐stratifying processes other ipRGC types. show that cells are by far most abundant labeled adult pigmented Cdh3‐GFP BAC transgenic mice. A few M5 ipRGCs also labeled, but no RGC types were encountered. Several distinct subnuclei geniculate complex pretectum contain retinofugal axons mouse. These presumably principle central targets (as well as cells). Projections from dorsal lateral nucleus confirmed retrograde tracing, suggesting they contribute pattern vision. low levels melanopsin expression relatively weak melanopsin‐dependent light responses. They exhibit strong synaptically driven Their fields smallest abundantly all ipRGCs. small receptive antagonistic surrounds. Despite deploying partly OFF sublamina, appear be exclusively ON pathway, their arbor, like those certain ipRGCs, may receive ectopic input passing bipolar sublayer.

Language: Английский

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Diverse Cell Types, Circuits, and Mechanisms for Color Vision in the Vertebrate Retina

Physiological Reviews, Journal Year: 2019, Volume and Issue: 99(3), P. 1527 - 1573

Published: May 29, 2019

Synaptic interactions to extract information about wavelength, and thus color, begin in the vertebrate retina with three classes of light-sensitive cells: rod photoreceptors at low light levels, multiple types cone that vary spectral sensitivity, intrinsically photosensitive ganglion cells contain photopigment melanopsin. When isolated from its neighbors, a photoreceptor confounds photon flux wavelength so by itself provides no color. The has evolved elaborate color opponent circuitry for extracting comparing activities different broadly tuned parts visible spectrum. We review studies concerning circuit mechanisms mediating range species, tetrachromatic fish diverse cell common dichromatic mammals where opponency is restricted subset specialized circuits. Distinct among mammals, primates have reinvented trichromatic vision using novel strategies incorporate evolution an additional gene into foveal structure supports high-resolution vision. Color absent scotopic levels when only rods are active, but interact signals influence perception mesopic levels. Recent evidence suggests melanopsin-mediated signals, which been identified as substrate setting circadian rhythms, may also perception. consider circuits mediate these interactions. While relatively simple neural computation, it implemented vertebrates not yet fully understood.

Language: Английский

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Diversity of intrinsically photosensitive retinal ganglion cells: circuits and functions

Cellular and Molecular Life Sciences, Journal Year: 2020, Volume and Issue: 78(3), P. 889 - 907

Published: Sept. 23, 2020

Language: Английский

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