From the desk of Poor publishers,
Sleepiness can be controlled by a set of nerve cells in the eye, tests on mice suggest, offering a new target for drug developers that may lead to better sleeping pills, British scientists said.
Light levels have long been known to affect alertness, which is why dimly lit rooms lead people to feel drowsy. But the biological mechanism for this has been unclear.
Now, Oxford university researchers have discovered that so called retinal ganglion cells play a key role. In mice, where these cells are turned off genetically, the effects of light on sleep and alertness is completely abolished.
Scientists have discovered a new pathway that modulates sleep and arousal. Scientists believe that if they can mimic the effect of light pharmacologically they could turn sleep on and off. Many drugs have been developed to modify sleep-wake cycles, creating a multibillion-a-year sleeping pill market. But the action of current medicines is relatively crude and the drugs have side effects.
By targeting the specific mechanism controlling the action of retinal ganglion cells, it may be possible in the future to develop much more sophisticated treatments. The researchers were able to track the sleep pathway to the brain, showing that two sleep inducing centers there were directlty activated by the cells.
The research however, is still at an early stage and scientists have yet to establish if the same processes affecting the back to front world of the mouse will work in humans. Because mice are nocturnal, the effects seen in the animal tests were opposite to those that would be expected in humans.
Mice normally sleep when it is light and wake up in the dark. But those mice in which the light sensitive cells were turned off stayed wide awake when the lights were on. - reports Reuters.
Sleepiness can be controlled by a set of nerve cells in the eye, tests on mice suggest, offering a new target for drug developers that may lead to better sleeping pills, British scientists said.
Light levels have long been known to affect alertness, which is why dimly lit rooms lead people to feel drowsy. But the biological mechanism for this has been unclear.
Now, Oxford university researchers have discovered that so called retinal ganglion cells play a key role. In mice, where these cells are turned off genetically, the effects of light on sleep and alertness is completely abolished.
Scientists have discovered a new pathway that modulates sleep and arousal. Scientists believe that if they can mimic the effect of light pharmacologically they could turn sleep on and off. Many drugs have been developed to modify sleep-wake cycles, creating a multibillion-a-year sleeping pill market. But the action of current medicines is relatively crude and the drugs have side effects.
By targeting the specific mechanism controlling the action of retinal ganglion cells, it may be possible in the future to develop much more sophisticated treatments. The researchers were able to track the sleep pathway to the brain, showing that two sleep inducing centers there were directlty activated by the cells.
The research however, is still at an early stage and scientists have yet to establish if the same processes affecting the back to front world of the mouse will work in humans. Because mice are nocturnal, the effects seen in the animal tests were opposite to those that would be expected in humans.
Mice normally sleep when it is light and wake up in the dark. But those mice in which the light sensitive cells were turned off stayed wide awake when the lights were on. - reports Reuters.
