Sleep switch discovered deep inside the brain

In a major breakthrough, scientists have found a sleep switch buried deep in the most primitive part of the brain. Neurons or brain cells located in this tiny region release a messenger chemical called GABA that sets of a series of steps leading to deep sleep. The discovery may lead to therapies for curing sleeplessness, a growing disorder across the world.

The discovery was made by researchers at Harvard School of Medicine and the University of Buffalo School of Medicine and Biomedical Sciences and published online in the August issue of Nature Neuroscience.

The sleep switch is located in the parafacial zone (PZ) in the brainstem. The brainstem is a primordial part of the brain that regulates basic functions necessary for survival, such as breathing, blood pressure, heart rate and body temperature. The study demonstrates that fully half of all of the brain's sleep-promoting activity originates from this zone. The activity of this "sleep node" appears to be both necessary and sufficient to produce deep sleep.

"The close association of a sleep center with other regions that are critical for life highlights the evolutionary importance of sleep in the brain," says Caroline E. Bass, assistant professor at the UB School of Medicine and Biomedical Sciences and a co-author on the paper.

The researchers found that a specific type of neuron in the PZ that makes the neurotransmitter gamma-aminobutyric acid (GABA) is responsible for deep sleep. They used a set of innovative tools to precisely control these neurons remotely, in essence giving them the ability to turn the neurons on and off at will.

"These new molecular approaches allow unprecedented control over brain function at the cellular level," says Christelle Ancelet, postdoctoral fellow at Harvard School of Medicine. "Before these tools were developed, we often used 'electrical stimulation' to activate a region, but the problem is that doing so stimulates everything the electrode touches and even surrounding areas it didn't. It was a sledgehammer approach, when what we needed was a scalpel."

"To get the precision required for these experiments, we introduced a virus into the PZ that expressed a 'designer' receptor on GABA neurons only but didn't otherwise alter brain function," explains Patrick Fuller, assistant professor at Harvard and senior author on the paper. "When we turned on the GABA neurons in the PZ, the animals quickly fell into a deep sleep without the use of sedatives or sleep aids."

How these neurons interact in the brain with other sleep and wake-promoting brain regions still need to be studied, the researchers say, but eventually these findings may translate into new medications for treating sleep disorders, including insomnia, and the development of better and safer anesthetics.

"We are at a truly transformative point in neuroscience," says Bass, "where the use of designer genes gives us unprecedented ability to control the brain. We can now answer fundamental questions of brain function, which have traditionally been beyond our reach, including the 'why' of sleep, one of the more enduring mysteries in the neurosciences."

Anda sedang membaca artikel tentang

Sleep switch discovered deep inside the brain

Dengan url

http://pijitwajah.blogspot.com/2014/10/sleep-switch-discovered-deep-inside_16.html

Anda boleh menyebar luaskannya atau mengcopy paste-nya

Sleep switch discovered deep inside the brain

namun jangan lupa untuk meletakkan link

Sleep switch discovered deep inside the brain

sebagai sumbernya