keyword
MENU ▼
Read by QxMD icon Read
search

Melanopsin

keyword
https://www.readbyqxmd.com/read/28801634/mapping-physiological-inputs-from-multiple-photoreceptor-systems-to-dopaminergic-amacrine-cells-in-the-mouse-retina
#1
Xiwu Zhao, Kwoon Y Wong, Dao-Qi Zhang
In the vertebrate retina, dopamine is synthesized and released by a specialized type of amacrine cell, the dopaminergic amacrine cell (DAC). DAC activity is stimulated by rods, cones, and melanopsin-expressing intrinsically photosensitive retinal ganglion cells upon illumination. However, the relative contributions of these three photoreceptor systems to the DAC light-induced response are unknown. Here we found that rods excite dark-adapted DACs across a wide range of stimulation intensities, primarily through connexin-36-dependent rod pathways...
August 11, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28782536/immunolesion-of-melanopsin-neurons-causes-gonadal-regression-in-pekin-drakes-anas-platyrhynchos-domesticus
#2
H Potter, E Alenciks, K Frazier, A Porter, G S Fraley
Several light sensitive receptors have been described in the avian brain that are thought to regulate the reproductive axis independently from the eyes and pineal gland.Recently, our lab has described the presence of three of these photoneuroendocrine systems in the Pekin duck: opsin, opsin 5, & melanopsin. We set out to test the hypothesis that melanopsin receptive neurons are necessary to maintain seasonal reproductive status along with growth and development in the Pekin drake. To accomplish these goals we first investigated 50-week-old Pekin drakes that were housed in the aviary at Hope College under long day length (18 hrs lights on) conditions in floor pens...
August 4, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28758193/melanopsin-ganglion-cell-outer-retinal-dendrites-morphologically-distinct-and-asymmetrically-distributed-in-the-mouse-retina
#3
Katelyn B Sondereker, Jessica R Onyak, Shakib W Islam, Christopher L Ross, Jordan M Renna
A small population of retinal ganglion cells express the photopigment melanopsin and function as autonomous photoreceptors. They encode global luminance levels critical for light-mediated non-image forming visual processes including circadian rhythms and the pupillary light reflex. There are five melanopsin ganglion cell subtypes (M1-M5). M1 and displaced M1 (M1d) cells have dendrites that ramify within the outermost layer of the inner plexiform layer (IPL). It was recently discovered that some melanopsin ganglion cells extend dendrites into the outer retina...
July 31, 2017: Journal of Comparative Neurology
https://www.readbyqxmd.com/read/28751938/led-lights-with-hidden-intensity-modulated-blue-channels-aiming-for-enhanced-subconscious-visual-responses
#4
Garen Vartanian, Kwoon Y Wong, Pei-Cheng Ku
A new form of light-emitting diode (LED) light suitable for general illumination is proposed to enhance subconscious, nonimage-forming visual responses, which are essential to our well-being. Pulsing light has been shown to reduce photoreceptor adaptation and elicit stronger subconscious visual responses at an indoor illumination level. Using the silent substitution technique, a melanopsin-selective flicker can be added into white light. A linear optimization algorithm was developed to suppress any perceivable fluctuation of light intensity and colors of illuminated objects...
June 2017: IEEE Photonics Journal
https://www.readbyqxmd.com/read/28716667/pupillometric-evaluation-of-the-melanopsin-containing-retinal-ganglion-cells-in-mitochondrial-and-non-mitochondrial-optic-neuropathies
#5
Shakoor Ba-Ali, Henrik Lund-Andersen
In recent years, chromatic pupillometry is used in humans to evaluate the activity of melanopsin expressing intrinsic photosensitive retinal ganglion cells (ipRGCs). Blue light is used to stimulate the ipRGCs and red light activates the rod/cone photoreceptors. The late re-dilation phase of pupillary light reflex is primarily driven by the ipRGCs. Optic neuropathies i.e. Leber hereditary optic neuropathy (LHON), autosomal dominant optic atrophy (ADOA), nonarteritic anterior ischemic optic neuropathy (NAION), glaucoma, optic neuritis and idiopathic intracranial hypertension (IIH) are among the diseases, which have been subject to pupillometric studies...
July 14, 2017: Mitochondrion
https://www.readbyqxmd.com/read/28708670/color-pupillography-in-dorsal-midbrain-syndrome
#6
Carina B Kelbsch, Fumiatsu Maeda, Torsten Strasser, Tobias M Peters, Barbara J C Wilhelm, Helmut M Wilhelm
OBJECTIVE: The purpose of this study was to evaluate the pupil response to chromatic stimuli in patients with lesions in the dorsal midbrain and possibly gain new insights into the afferent pupillary pathways. METHODS: Color pupillography was performed in 5 patients with dorsal midbrain syndrome (DMS), and their results were compared with those of 20 healthy control subjects. We used full-field red stimuli (605 nm) that primarily address the rod/cone system and blue stimuli (420 nm) that preferentially activate intrinsically photosensitive retinal ganglion cells (ipRGCs) directly, with a duration of 4 seconds and a stimulus intensity of 28 lx corneal illumination under mesopic conditions...
September 2017: Journal of Neuro-ophthalmology: the Official Journal of the North American Neuro-Ophthalmology Society
https://www.readbyqxmd.com/read/28697776/exposure-to-blue-light-during-lunch-break-effects-on-autonomic-arousal-and-behavioral-alertness
#7
Emi Yuda, Hiroki Ogasawara, Yutaka Yoshida, Junichiro Hayano
BACKGROUND: Exposures to melanopsin-stimulating (melanopic) component-rich blue light enhance arousal level. We examined their effects in office workers. Eight healthy university office workers were exposed to blue and orange lights for 30 min during lunch break on different days. We compared the effects of light color on autonomic arousal level assessed by heart rate variability (HRV) and behavioral alertness by psychomotor vigilance tests (PVT). Heart rate was higher and high-frequency (HF, 0...
July 11, 2017: Journal of Physiological Anthropology
https://www.readbyqxmd.com/read/28697361/vision-melanopsin-as-a-raumgeber
#8
Manuel Spitschan, Geoffrey K Aguirre
Two new studies show that neural systems receiving inputs from the melanopsin-containing retinal ganglion cells encode spatial information and therefore see the world in more detail than previously thought.
July 10, 2017: Current Biology: CB
https://www.readbyqxmd.com/read/28660274/pupillary-light-reflexes-in-severe-photoreceptor-blindness-isolate-the-melanopic-component-of-intrinsically-photosensitive-retinal-ganglion-cells
#9
Jason Charng, Samuel G Jacobson, Elise Heon, Alejandro J Roman, David B McGuigan, Rebecca Sheplock, Mychajlo S Kosyk, Malgorzata Swider, Artur V Cideciyan
Purpose: Pupillary light reflex (PLR) is driven by outer retinal photoreceptors and by melanopsin-expressing intrinsically photosensitive retinal ganglion cells of the inner retina. To isolate the melanopic component, we studied patients with severe vision loss due to Leber congenital amaurosis (LCA) caused by gene mutations acting on the outer retina. Methods: Direct PLR was recorded in LCA patients (n = 21) with known molecular causation and severe vision loss...
June 1, 2017: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/28649427/global-rise-of-potential-health-hazards-caused-by-blue-light-induced-circadian-disruption-in-modern-aging-societies
#10
REVIEW
Megumi Hatori, Claude Gronfier, Russell N Van Gelder, Paul S Bernstein, Josep Carreras, Satchidananda Panda, Frederick Marks, David Sliney, Charles E Hunt, Tsuyoshi Hirota, Toshiharu Furukawa, Kazuo Tsubota
Mammals receive light information through the eyes, which perform two major functions: image forming vision to see objects and non-image forming adaptation of physiology and behavior to light. Cone and rod photoreceptors form images and send the information via retinal ganglion cells to the brain for image reconstruction. In contrast, nonimage-forming photoresponses vary widely from adjustment of pupil diameter to adaptation of the circadian clock. nonimage-forming responses are mediated by retinal ganglion cells expressing the photopigment melanopsin...
2017: NPJ Aging and Mechanisms of Disease
https://www.readbyqxmd.com/read/28642483/masking-of-a-circadian-behavior-in-larval-zebrafish-involves-the-thalamo-habenula-pathway
#11
Qian Lin, Suresh Jesuthasan
Changes in illumination can rapidly influence behavior that is normally controlled by the circadian clock. This effect is termed masking. In mice, masking requires melanopsin-expressing retinal ganglion cells that detect blue light and project to the thalamus. It is not known whether masking is wavelength-dependent in other vertebrates, nor is it known whether the thalamus is also involved or how it influences masking. Here, we address these questions in zebrafish. We find that diel vertical migration, a circadian behavior in larval zebrafish, is effectively triggered by blue, but not by red light...
June 22, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28641988/wavy-multistratified-amacrine-cells-in-the-monkey-retina-contain-immunoreactive-secretoneurin
#12
Andrea S Bordt, Ye Long, Nobuo Kouyama, Elizabeth S Yamada, Jens Hannibal, David W Marshak
The goals of this study were to describe the morphology, neurotransmitter content and synaptic connections of neurons in primate retinas that contain the neuropeptide secretoneurin. Amacrine cells were labeled with antibodies to secretoneurin in macaque and baboon retinas. Their processes formed three distinct plexuses in the inner plexiform layer: one in the outermost stratum, one in the center and one in the innermost stratum. In light microscopic double immunolabeling experiments, GABA was colocalized with secretoneurin in these cells, but glycine transporter 1 and Substance P were not...
August 2017: Peptides
https://www.readbyqxmd.com/read/28634329/long-days-enhance-recognition-memory-and-increase-insulin-like-growth-factor-2-in-the-hippocampus
#13
Adriano Dellapolla, Ian Kloehn, Harshida Pancholi, Ben Callif, David Wertz, Kayla E Rohr, Matthew M Hurley, Kimberly M Baker, Samer Hattar, Marieke R Gilmartin, Jennifer A Evans
Light improves cognitive function in humans; however, the neurobiological mechanisms underlying positive effects of light remain unclear. One obstacle is that most rodent models have employed lighting conditions that cause cognitive deficits rather than improvements. Here we have developed a mouse model where light improves cognitive function, which provides insight into mechanisms underlying positive effects of light. To increase light exposure without eliminating daily rhythms, we exposed mice to either a standard photoperiod or a long day photoperiod...
June 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28589149/dexamethasone-modulates-nonvisual-opsins-glucocorticoid-receptor-and-clock-genes-in-danio-rerio-zem-2s-cells
#14
Jennifer Caroline Sousa, Keila Karoline Magalhães-Marques, Sanseray da Silveira Cruz-Machado, Maria Nathalia Moraes, Ana Maria de Lauro Castrucci
Here we report, for the first time, the differential cellular distribution of two melanopsins (Opn4m1 and Opn4m2) and the effects of GR agonist, dexamethasone, on the expression of these opsins and clock genes, in the photosensitive D. rerio ZEM-2S embryonic cells. Immunopositive labeling for Opn4m1 was detected in the cell membrane whereas Opn4m2 labeling shows nuclear localization, which did not change in response to light. opn4m1, opn4m2, gr, per1b, and cry1b presented an oscillatory profile of expression in LD condition...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28578927/synergistic-signaling-by-light-and-acetylcholine-in-mouse-iris-sphincter-muscle
#15
Qian Wang, Wendy Wing Sze Yue, Zheng Jiang, Tian Xue, Shin H Kang, Dwight E Bergles, Katsuhiko Mikoshiba, Stefan Offermanns, King-Wai Yau
The mammalian pupillary light reflex (PLR) involves a bilateral brain circuit whereby afferent light signals in the optic nerve ultimately drive iris-sphincter-muscle contraction via excitatory cholinergic parasympathetic innervation [1, 2]. Additionally, the PLR in nocturnal and crepuscular sub-primate mammals has a "local" component in the isolated sphincter muscle [3-5], as in amphibians, fish, and bird [6-10]. In mouse, this local PLR requires the pigment melanopsin [5], originally found in intrinsically photosensitive retinal ganglion cells (ipRGCs) [11-19]...
June 19, 2017: Current Biology: CB
https://www.readbyqxmd.com/read/28552384/light-induced-retinal-degeneration-causes-a-transient-downregulation-of-melanopsin-in-the-rat-retina
#16
Diego García-Ayuso, Caridad Galindo-Romero, Johnny Di Pierdomenico, Manuel Vidal-Sanz, Marta Agudo-Barriuso, María P Villegas Pérez
In this work we study the effects of an acute light-induced retinal degeneration on the population of melanopsin positive retinal ganglion cells (m(+)RGCs) and the expression of the melanopsin protein in the retina. The m(+)RGCs may be more resistant than other RGCs to lesion, but the effects of an acute light exposure in this population are unknown. Albino rats were exposed to white light (3000 lux) continuously for 48 h and processed 0, 3, 7 or 30 days after light exposure (ALE). Whole-mounted retinas were immunodetected with antibodies against melanopsin, Brn3a, and rhodopsin to study the populations of m(+)RGC, Brn3a(+)RGC and rods (which are the most abundant photoreceptors in the rat retina)...
August 2017: Experimental Eye Research
https://www.readbyqxmd.com/read/28549093/autoantibodies-in-melanoma-associated-retinopathy-recognize-an-epitope-conserved-between-trpm1-and-trpm3
#17
Robert M Duvoisin, Tammie L Haley, Gaoying Ren, Iwona Strycharska-Orczyk, James P Bonaparte, Catherine W Morgans
Purpose: Melanoma-associated retinopathy (MAR) is a paraneoplastic syndrome associated with malignant melanoma and the presence of anti-retinal autoantibodies, including autoantibodies against transient receptor potential melanopsin 1 (TRPM1), a cation channel expressed by both melanocytes and retinal bipolar cells. The goal of this study was to further map the antigenic epitope. Methods: Patient sera were tested by immunofluorescence and Western blotting on HEK293 cells transfected with enhanced green fluorescent protein (EGFP)-TRPM1 fusion constructs and mouse retina sections...
May 1, 2017: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/28545362/insight-into-the-role-of-photoreception-and-light-intervention-for-sleep-and-neuropsychiatric-behaviour-in-the-elderly
#18
Katharina Wulff, Russell G Foster
Light exerts influences on many physiological and behavioural functions in humans. These functions can be described as image-forming (IF) and non-image forming (NIF) visual processes, both originating in the retina of the eye. Image-forming refers to vision; the process of detecting and distinguishing shapes and colour of objects. Non-image forming refers to detecting level of light intensity or brightness of ambient space, which affects basal physiology such as cycles of rest and activity or the endocrine system...
May 22, 2017: Current Alzheimer Research
https://www.readbyqxmd.com/read/28545361/applying-melanopic-lux-to-measure-biological-light-effects-on-melatonin-suppression-and-subjective-sleepiness
#19
Claudia Nowozin, Amely Wahnschaffe, Andrea Rodenbeck, Jan de Zeeuw, Sven Hädel, Ruslan Kozakov, Heinz Schöpp, Mirjam Münch, Dieter Kunz
In the beginning of this century a novel photopigment, melanopsin, was discovered in a sub-class of retinal ganglion cells and its action spectrum was described. Shortly after, it became clear that melanopsin is one major contributor to non-visual eye-mediated effects of light on e.g. the circadian, neuroendocrine and neurobehavioral systems. First applied studies pointed out that these non-visual effects of light are relevant for wellbeing, performance and general health. A standardized measurement quantity for these non-visual effects does not exist, but would ease application...
May 22, 2017: Current Alzheimer Research
https://www.readbyqxmd.com/read/28535270/intrinsically-photosensitive-retinal-ganglion-cell-function-sleep-efficiency-and-depression-in-advanced-age-related-macular-degeneration
#20
Michelle L Maynard, Andrew Zele, Anthony Kwan, Beatrix Feigl
Purpose: Melanopsin expressing intrinsically photosensitive retinal ganglion cells (ipRGC) input to multiple brain regions including those for pupil control, circadian rhythms, sleep and mood regulation. Here we measured ipRGC function and its relationship to sleep quality and depression in patients with advanced AMD. Methods: The melanopsin-mediated post-illumination pupil response (PIPR) was measured in 53 patients with advanced AMD (age 78.8 ± 8.8 years) and in 20 healthy controls (age 72...
February 1, 2017: Investigative Ophthalmology & Visual Science
keyword
keyword
38087
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"