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Felix L Struebing, Richard K Lee, Robert W Williams, Eldon E Geisert
Retinal ganglion cells (RGCs) are the output neuron of the eye, transmitting visual information from the retina through the optic nerve to the brain. The importance of RGCs for vision is demonstrated in blinding diseases where RGCs are lost, such as in glaucoma or after optic nerve injury. In the present study, we hypothesize that normal RGC function is transcriptionally regulated. To test our hypothesis, we examine large retinal expression microarray datasets from recombinant inbred mouse strains in GeneNetwork and define transcriptional networks of RGCs and their subtypes...
2016: Frontiers in Genetics
Shaobo Lei, Herbert C Goltz, Jaime C Sklar, Agnes M F Wong
We collected and analyzed pupil diameter data from of 7 visually normal participants to compare the maximum pupil constriction (MPC) induced by "Red Only" vs. "Blue+Red" visual stimulation conditions. The "Red Only" condition consisted of red light (640±10 nm) stimuli of variable intensity and duration presented to dark-adapted eyes with pupils at resting state. This condition stimulates the cone-driven activity of the intrinsically photosensitive retinal ganglion cells (ipRGC). The "Blue+Red" condition consisted of the same red light stimulus presented during ongoing blue (470±17 nm) light-induced post-illumination pupil response (PIPR), representing the cone-driven ipRGC activity superimposed on the melanopsin-driven intrinsic activity of the ipRGCs ("The Absence of Attenuating Effect of Red light Exposure on Pre-existing Melanopsin-Driven Post-illumination Pupil Response" Lei et al...
September 2016: Data in Brief
Pablo A Barrionuevo, Dingcai Cao
Intrinsically photosensitive retinal ganglion cells (ipRGCs) express the photopigment melanopsin. These cells receive afferent inputs from rods and cones, which provide inputs to the postreceptoral visual pathways. It is unknown, however, how melanopsin activation is integrated with postreceptoral signals to control the pupillary light reflex. This study reports human flicker pupillary responses measured using stimuli generated with a five-primary photostimulator that selectively modulated melanopsin, rod, S-, M-, and L-cone excitations in isolation, or in combination to produce postreceptoral signals...
September 1, 2016: Journal of Vision
Shao-Min Hung, Dan Milea, Annadata Venkata Rukmini, Raymond P Najjar, Joo Huang Tan, Françoise Viénot, Marie Dubail, Sharon Lee Choon Tow, Tin Aung, Joshua J Gooley, Po-Jang Hsieh
Photic stimulation of rods, cones and intrinsically photosensitive melanopsin-containing retinal ganglion cells (ipRGCs) mediates non-visual light responses, including entrainment of circadian rhythms and pupillary light reflex. Unlike visual responses to photic stimulation, the cerebral correlates of non-visual light responses in humans remains elusive. In this study, we used functional magnetic resonance imaging (fMRI) in 14 healthy young participants, to localize cerebral regions which are differentially activated by metameric light that gave rise to different levels of melanopic excitation...
September 26, 2016: NeuroImage
William Thomas Keenan, Alan C Rupp, Rachel A Ross, Preethi Somasundaram, Suja Hiriyanna, Zhijian Wu, Tudor C Badea, Phyllis R Robinson, Bradford B Lowell, Samer S Hattar
Rapid and stable control of pupil size in response to light is critical for vision, but the neural coding mechanisms remain unclear. Here, we investigated the neural basis of pupil control by monitoring pupil size across time while manipulating each photoreceptor input or neurotransmitter output of intrinsically photosensitive retinal ganglion cells (ipRGCs), a critical relay in the control of pupil size. We show that transient and sustained pupil responses are mediated by distinct photoreceptors and neurotransmitters...
September 26, 2016: ELife
Maria Angeles Bonmati-Carrion, Konstanze Hild, Cheryl Isherwood, Stephen J Sweeney, Victoria L Revell, Debra J Skene, Maria Angeles Rol, Juan Antonio Madrid
Intrinsically photosensitive retinal ganglion cells (ipRGCs), whose photopigment melanopsin has a peak of sensitivity in the short wavelength range of the spectrum, constitute a common light input pathway to the olivary pretectal nucleus (OPN), the pupillary light reflex (PLR) regulatory centre, and to the suprachiasmatic nuclei (SCN), the major pacemaker of the circadian system. Thus, evaluating PLR under short wavelength light (λmax ≤ 500 nm) and creating an integrated PLR parameter, as a possible tool to indirectly assess the status of the circadian system, becomes of interest...
2016: PloS One
Anna Matynia, Eileen Nguyen, Xiaoping Sun, Frank W Blixt, Sachin Parikh, Jason Kessler, Luis Pérez de Sevilla Müller, Samer Habib, Paul Kim, Zhe Z Wang, Allen Rodriguez, Andrew Charles, Steven Nusinowitz, Lars Edvinsson, Steven Barnes, Nicholas C Brecha, Michael B Gorin
The ability of light to cause pain is paradoxical. The retina detects light but is devoid of nociceptors while the trigeminal sensory ganglia (TG) contain nociceptors but not photoreceptors. Melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs) are thought to mediate light-induced pain but recent evidence raises the possibility of an alternative light responsive pathway independent of the retina and optic nerve. Here, we show that melanopsin is expressed in both human and mouse TG neurons...
2016: Frontiers in Neural Circuits
Prakash Adhikari, Beatrix Feigl, Andrew J Zele
Melanopsin expressing intrinsically photosensitive Retinal Ganglion Cells (ipRGCs) entirely control the post-illumination pupil response (PIPR) from 6 s post-stimulus to the plateau during redilation after light offset. However, the photoreceptor contributions to the early redilation phase of the PIPR (< 6 s post-stimulus) have not been reported. Here, we evaluated the photoreceptor contributions to the early phase PIPR (0.6 s to 5.0 s) by measuring the spectral sensitivity of the criterion PIPR amplitude in response to 1 s light pulses at five narrowband stimulus wavelengths (409, 464, 508, 531 and 592 nm)...
2016: PloS One
Manami Kuze, Takeshi Morita, Yumi Fukuda, Mineo Kondo, Kazuo Tsubota, Masahiko Ayaki
PURPOSE: To record electroretinograms (ERGs) from intrinsically photosensitive retinal ganglion cells (ipRGCs) of glaucoma patients. METHODS: ERGs were recorded in 10 normal subjects and 15 patients with glaucoma. The ERG illumination system was built to achieve receptor-silent substitution, and comprised an optical diffuser and four-in-one light-emitting diodes. RESULTS: The ERG recordings of ipRGC from normal subjects showed an "on" response and an "off" response...
August 16, 2016: Journal of Optometry
Phillip T Yuhas, Patrick D Shorter, Catherine E McDaniel, Michael J Earley, Andrew T E Hartwick
PURPOSE: Photophobia is a common symptom in individuals suffering from traumatic brain injury (TBI). Recent evidence has implicated blue light-sensitive intrinsically photosensitive retinal ganglion cells (ipRGCs) in contributing to the neural circuitry mediating photophobia in migraine sufferers. The goal of this work is to test the hypothesis that ipRGC function is altered in TBI patients with photophobia by assessing pupillary responses to blue and red light. METHODS: Twenty-four case participants (mean age 43...
July 23, 2016: Optometry and Vision Science: Official Publication of the American Academy of Optometry
Ouafa Ait-Hmyed Hakkari, Niyazi Acar, Elise Savier, Perrine Spinnhirny, Mohammed Bennis, Marie-Paule Felder-Schmittbuhl, Jorge Mendoza, David Hicks
The circadian clock is thought to adjust retinal sensitivity to ambient light levels, yet the involvement of specific clock genes is poorly understood. We explored the potential role of the nuclear receptor subfamily 1, group D, member 1 (REV-ERBα; or NR1D1) in this respect. In light-evoked behavioral tests, compared with wild-type littermates, Rev-Erbα(-/-) mice showed enhanced negative masking at low light levels (0.1 lux). Rev-Erbα(-/-) mouse retinas displayed significantly higher numbers of intrinsically photosensitive retinal ganglion cells (ipRGCs; 62% more compared with wild-type) and more intense melanopsin immunostaining of individual ipRGC cells...
July 20, 2016: FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology
Miguel Dasilva, Riccardo Storchi, Katherine E Davis, Kenneth L Grieve, Robert J Lucas
Melanopsin phototransduction allows intrinsically photosensitive retinal ganglion cells (ipRGCs) to maintain firing under sustained illumination and to encode irradiance. ipRGCs project to different parts of the visual system, including the superficial superior colliculus (sSC), but to date there is no description of melanopsin contributions to the activity of that nucleus. We sought to fill that gap using extracellular recordings to describe light response in the sSC. We failed to observe light responses in the sSC of mice lacking rod and cone function, in which melanopsin provides the only photoreception...
September 2016: European Journal of Neuroscience
Cameron L Prigge, Po-Ting Yeh, Nan-Fu Liou, Chi-Chan Lee, Shih-Feng You, Lei-Lei Liu, David S McNeill, Kylie S Chew, Samer Hattar, Shih-Kuo Chen, Dao-Qi Zhang
UNLABELLED: Melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs, with five subtypes named M1-M5) are a unique subclass of RGCs with axons that project directly to many brain nuclei involved in non-image-forming functions such as circadian photoentrainment and the pupillary light reflex. Recent evidence suggests that melanopsin-based signals also influence image-forming visual function, including light adaptation, but the mechanisms involved are unclear. Intriguingly, a small population of M1 ipRGCs have intraretinal axon collaterals that project toward the outer retina...
July 6, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Takuma Sonoda, Tiffany M Schmidt
Recently, researchers identified a novel ganglion cell photoreceptor in vertebrates, called intrinsically photosensitive retinal ganglion cells (ipRGCs). These ipRGCs are photosensitive due to expression of a photopigment, melanopsin. Although ipRGCs were initially thought to be a uniform population of cells involved solely in subconscious, non-image forming behaviors, recent research points to a role for ipRGCs in pattern vision. Here we highlight the emerging evidence for this influence of ipRGCs on pattern vision and discuss important future directions for understanding this newly appreciated contribution of melanopsin signaling to visual processing...
July 1, 2016: Integrative and Comparative Biology
David A Arroyo, Lowry A Kirkby, Marla B Feller
UNLABELLED: Before the maturation of rod and cone photoreceptors, the developing retina relies on light detection by intrinsically photosensitive retinal ganglion cells (ipRGCs) to drive early light-dependent behaviors. ipRGCs are output neurons of the retina; however, they also form functional microcircuits within the retina itself. Whether ipRGC microcircuits exist during development and whether they influence early light detection remain unknown. Here, we investigate the neural circuit that underlies the ipRGC-driven light response in developing mice...
June 29, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Sheng-Nan Qiao, Zhijing Zhang, Christophe P Ribelayga, Yong-Mei Zhong, Dao-Qi Zhang
Dopamine is a key neurotransmitter in the retina and plays a central role in the light adaptive processes of the visual system. The sole source of retinal dopamine is dopaminergic amacrine cells (DACs). We and others have previously demonstrated that DACs are activated by rods, cones, and intrinsically photosensitive retinal ganglion cells (ipRGCs) upon illumination. However, it is still not clear how each class of photosensitive cells generates light responses in DACs. We genetically isolated cone function in mice to specifically examine the cone-mediated responses of DACs and their neural pathways...
2016: Scientific Reports
Daniel S Joyce, Beatrix Feigl, Andrew J Zele
Intrinsically photosensitive retinal ganglion cells (ipRGCs) regulate pupil size by integrating extrinsic rod and cone signals with intrinsic melanopsin-mediated phototransduction. Light adapted pupil diameter is determined by the corneal flux density (CFD), and for central visual field stimulation the melanopsin-mediated post-illumination pupil response (PIPR) follows this same CFD relationship. Rods, cones, and ipRGCs vary in size, density, and distribution across the retina, but how these differences affect the amplitude and timing of the extrinsic and intrinsic pupil light reflex in the central and peripheral retina is unknown...
June 1, 2016: Journal of Vision
Ludovic S Mure, Megumi Hatori, Quansheng Zhu, James Demas, Irene M Kim, Surendra K Nayak, Satchidananda Panda
Melanopsin photopigment expressed in intrinsically photosensitive retinal ganglion cells (ipRGCs) plays a crucial role in the adaptation of mammals to their ambient light environment through both image-forming and non-image-forming visual responses. The ipRGCs are structurally and functionally distinct from classical rod/cone photoreceptors and have unique properties, including single-photon response, long response latency, photon integration over time, and slow deactivation. We discovered that amino acid sequence features of melanopsin protein contribute to the functional properties of the ipRGCs...
June 1, 2016: Neuron
Diego Carlos Fernandez, Yi-Ting Chang, Samer Hattar, Shih-Kuo Chen
The suprachiasmatic nucleus (SCN) receives direct retinal input from the intrinsically photosensitive retinal ganglion cells (ipRGCs) for circadian photoentrainment. Interestingly, the SCN is the only brain region that receives equal inputs from the left and right eyes. Despite morphological assessments showing that axonal fibers originating from ipRGCs cover the entire SCN, physiological evidence suggests that only vasoactive intestinal polypeptide (VIP)/gastrin-releasing peptide (GRP) cells located ventrally in the SCN receive retinal input...
May 24, 2016: Proceedings of the National Academy of Sciences of the United States of America
Carina Kelbsch, Fumiatsu Maeda, Torsten Strasser, Gunnar Blumenstock, Barbara Wilhelm, Helmut Wilhelm, Tobias Peters
PURPOSE: The aim was to investigate the involvement of intrinsically photosensitive retinal ganglion cells (ipRGCs) in patients with manifest glaucoma and ocular hypertension (OH) using specific parameters of the pupil light reflex to chromatic stimuli. METHODS: Twenty-five patients with manifest glaucoma, 16 patients with OH and 16 healthy control subjects were stimulated with 28 lx red (605 nm) or blue (420 nm) light with a duration of either 1 s or 4 s. The consensual pupil light reaction was recorded by means of infrared pupillometry...
July 2016: Graefe's Archive for Clinical and Experimental Ophthalmology
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