Results 181 to 190 of about 6,987 (212)

Melanopsin in the Circadian Timing System

Journal of Molecular Neuroscience, 2003
In mammals, circadian rhythms are generated by a light-entrainable oscillator located in the hypothalamic suprachiasmatic nucleus (SCN). Light signals reach the SCN via a dedicated retinal pathway, the retinohypothalamic tract (RHT). One question that continues to elude scientists is whether the circadian system has its own dedicated photoreceptor or ...
Christian, Beaulé, Barry, Robinson, Elaine Waddington, Lamont, Shimon, Amir   +3 more
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Regulation of Melanopsin Expression

Chronobiology International, 2006
Circadian rhythms in mammals are adjusted daily to the environmental day/night cycle by photic input via the retinohypothalamic tract (RHT). Retinal ganglion cells (RGCs) of the RHT constitute a separate light-detecting system in the mammalian retina used for irradiance detection and for transmission to the circadian system and other non-imaging ...
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Photochemical Properties of Mammalian Melanopsin

Biochemistry, 2012
Melanopsin is the photoreceptor molecule of intrinsically photosensitive retinal ganglion cells, which serve as the input for various nonvisual behavior and physiological functions fundamental to organisms. The retina, therefore, possess a melanopsin-based nonvisual system in addition to the visual system based on the classical visual photoreceptor ...
Take, Matsuyama, Takahiro, Yamashita, Yasushi, Imamoto, Yoshinori, Shichida   +3 more
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Melanopsin modulates refractive development and myopia

Experimental Eye Research, 2022
Myopia, or nearsightedness, is the most common form of refractive abnormality and is characterized by excessive ocular elongation in relation to ocular power. Retinal neurotransmitter signaling, including dopamine, is implicated in myopic ocular growth, but the visual pathways that initiate and sustain myopia remain unclear.
Ranjay Chakraborty, Erica G. Landis, Reece Mazade, Victoria Yang, Ryan Strickland, Samer Hattar, Richard A. Stone, P. Michael Iuvone, Machelle T. Pardue   +8 more
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Melanopsin and non-melanopsin expressing retinal ganglion cells innervate the hypothalamic suprachiasmatic nucleus

Visual Neuroscience, 2003
Retinal input to the hypothalamic suprachiasmatic nucleus (SCN) synchronizes the SCN circadian oscillator to the external day/night cycle. Retinal ganglion cells that innervate the SCNviathe retinohypothalamic tract are intrinsically light sensitive and express melanopsin.
Patricia J, Sollars, Cynthia A, Smeraski, Jessica D, Kaufman, Malcolm D, Ogilvie, Ignacio, Provencio, Gary E, Pickard   +5 more
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Melanopsin and other novel mammalian opsins

Experimental Eye Research, 2005
Within the past decade, several non-canonical opsins have been identified in mammals. These include RGR, peropsin, melanopsin, encephalopsin, and neuropsin. Although all are expressed in the eye, it is likely that they serve to mediate non-visual effects of light on physiology.
Tida, Kumbalasiri, Ignacio, Provencio
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Induction of photosensitivity by heterologous expression of melanopsin

Nature, 2005
Melanopsin has been proposed to be the photopigment of the intrinsically photosensitive retinal ganglion cells (ipRGCs); these photoreceptors of the mammalian eye drive circadian and pupillary adjustments through direct projections to the brain. Their action spectrum (lambda(max) approximately 480 nm) implicates an opsin and melanopsin is the only ...
Xudong, Qiu, Tida, Kumbalasiri, Stephanie M, Carlson, Kwoon Y, Wong, Vanitha, Krishna, Ignacio, Provencio, David M, Berson   +6 more
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Responding to Light with Melanopsin

Science's STKE, 2005
Certain mammalian retinal ganglion cells that express melanopsin act as photoreceptors that regulate circadian and pupillary responses. Although melanopsin is required for the photosensitivity of these cells, and has been proposed to act as a photopigment, its exact function has been uncertain. Two groups, Qiu et al
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Melanopsin in cells of origin of the retinohypothalamic tract

Nature Neuroscience, 2001
All known eukaryotic organisms exhibit physiological and behavioral rhythms termed circadian rhythms that cycle with a near-24-hour period; in mammals, light is the most potent stimulus for entraining endogenous rhythms to the daily light cycle. Photic information is transmitted via the retinohypothalamic tract (RHT) to the suprachiasmatic nucleus (SCN)
J J, Gooley, J, Lu, T C, Chou, T E, Scammell, C B, Saper   +4 more
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[Pupil and melanopsin photoreception].

Nippon Ganka Gakkai zasshi, 2013
The iris is the most anterior portion of the uveal tract. The pupil is round opening near the center of the iris; it is displaced slightly downward and nasally with respect to the center of the cornea. The mammalian iris sphincter is considered to be innervated by cholinergic, and the dilator muscle by adrenergic excitatory nerve fibers, and both ...
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