Navigation Links
Light receptors in eye play key role in setting biological clock, study shows
Date:8/15/2008

Biologists at the University of Virginia have discovered a switching mechanism in the eye that plays a key role in regulating the sleep/wake cycles in mammals.

The new finding demonstrates that light receptor cells in the eye are central to setting the rhythms of the brain's primary timekeeper, the suprachiasmatic nuclei, which regulates activity and rest cycles.

"The finding is significant because it changes our understanding of how light input from the eye can affect activity and sleep patterns," said Susan Doyle, a research scientist at U.Va. and the study's lead investigator.

The finding appears in the current issue of the Proceedings of the National Academy of Sciences.

The U.Va. researchers discovered that they could reverse the "temporal niche" of mice meaning that the animals' activity phase could be switched from their normal nocturnality, or night activity, to being diurnal, or day active.

The investigators did this by both reducing the intensity of light given to normal mice, and also creating a new line of mutated mice with reduced light sensitivity in their eyes, which rendered them fully active in the day but inactive at night, a complete reversal of the normal activity/rest cycles of mice.

"This suggests that we have discovered an additional mechanism for regulating nocturnity and diurnity that is located in the light input pathways of the eye," Doyle said. "The significance of this research for humans is that it could ultimately lead to new treatments for sleep disorders, perhaps even eye drops that would target neural pathways to the brain's central timekeeper."

Biological clocks are the body's complex network of internal oscillators that regulate daily activity/rest cycles and other important aspects of physiology, including body temperature, heart rate and food intake. Besides sleep disorders, research in this field may eventually help treat the negative effects of shift work, aging and jet lag.

About 20 to 25 percent of U.S. workers are shift workers, many of whom have difficulty sleeping during the day when they are not working, and likewise find it hard to stay alert at night while on the job.

An estimated one in six people in the United States suffer from sleep disorders, including insomnia and excessive sleepiness. And as the U.S. population ages, a growing number of people are developing visual impairments that can result in sleep disorders.

"Currently, one in 28 Americans age 40 and over suffer from blindness or low vision, and this number is estimated to double in the next 15 years," Doyle said. "Our discovery of the switching mechanism in the eye has direct relevance with respect to the eventual development of therapies to treat circadian and sleep disorders in the visually impaired."


'/>"/>
Contact: Susan Doyle
sed5c@virginia.edu
434-982-5768
University of Virginia
Source:Eurekalert

Related biology news :

1. Microbes, by latitudes and altitudes, shed new light on lifes diversity
2. AGU journal highlights -- August 6, 2008
3. Cold Spring Harbor Protocols highlights gene silencing, cancer cell biology methods
4. Highlights from the August 2008 Journal of the American Dietetic Association
5. New study spotlights National Institutes of Health grant outcomes for clinical research
6. AGU journal highlights -- July 23, 2008
7. August 2008 Geology and GSA Today media highlights
8. Meeting to highlight health impacts of smell and taste
9. Y chromosome study sheds light on Athapaskan migration to southwest US
10. Senate resolution shines spotlight on the importance of soils
11. Highlights from the July 2008 Journal of the American Dietetic Association
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:11/19/2016)... DALLAS , Nov. 18, 2016 Securus ... technology solutions for public safety, investigation, corrections and monitoring, ... a smaller competitor, ICSolutions, to have an independent technology ... set, the most modern high tech/sophisticated telephone calling platform, ... tell customers that they do most of what we ...
(Date:11/15/2016)... 15, 2016  Synthetic Biologics, Inc. (NYSE MKT: ... on the gut microbiome, today announced the pricing ... of its common stock and warrants to purchase ... price to the public of $1.00 per share ... from the offering, excluding the proceeds, if any ...
(Date:6/27/2016)... Research and Markets has announced the addition of the ... offering. The report forecasts the ... at a CAGR of 12.28% during the period 2016-2020. ... analysis with inputs from industry experts. The report covers the market ... also includes a discussion of the key vendors operating in this ...
Breaking Biology News(10 mins):
(Date:12/4/2016)... BELLINGHAM, Washington, USA (PRWEB) , ... December 02, ... ... the role of innovative U.S.-owned and -operated small businesses in federally funded research ... SPIE, the international society for optics and photonics . , As part ...
(Date:12/2/2016)... 2, 2016 More than $4.3 million was raised ... ( DHMD ). The gala was held at the American ... City and honored Alan Alda and ... health and medicine and the public understanding of science. Since ... the event has raised $40 million for the Laboratory,s research ...
(Date:12/2/2016)... ... ... ACEA Biosciences, Inc. announced today that it will be presenting updated efficacy ... Conference on Lung Cancer 2016, taking place in Vienna, Austria December 3rd-8th. , ... AC0010 in patients with advanced non-small cell lung cancer harboring the EGFR T790M resistance ...
(Date:12/2/2016)... ... , ... DrugDev believes the only way to achieve real change ... three tenets were on display at the 2nd Annual DrugDev User Summit (hosted by ... and site organizations to discuss innovation and the future of clinical research. , ...
Breaking Biology Technology: