Sleep is important for recovery but many scrimp on rest because of day-to-day activities. The body can't go more than a few days without sleep and when it's near its limit, the brain takes matters into its own hands and induces deep sleep. Researchers have found that how the brain naturally induces deep sleep and how sedatives work are similar.
In a study published in the journal Nature Neuroscience, researchers have found that some sedatives work by stimulating neurons in the preoptic hypothalamus. And when this part of the brain is activated, it then shuts down other areas, leading to deep sleep. With the discovery that sedatives actually affect just one part of the brain, researchers can aid in the creation of better-targeted sleeping aids and sedatives. These new drugs can directly tap into the preoptic hypothalamus to bring about more effective sedation, with shorter recovery times and fewer harmful side effects.
"If you don't sleep for a long period, your body shuts down - almost as if you had taken a drug. We've shown that sedative drugs trigger the same neurons, making the two types of unconsciousness very similar," explained Bill Wisden, a professor from Imperial College London and one of the authors for the study.
While many sedatives are undoubtedly effective, there remains a lot of gaps in what researchers know about what the drugs actually do to the brain. Wisden and colleagues looked into a common class of sedatives used in minor operations and discovered that many believed the drugs work by shutting down neural pathways.
To show how sedatives actually work, the researchers utilized a gene tagging system that marked neurons in the brains of mice activated when sedatives are administered and during recovery sleep. When researchers targeted the neurons that were activated during sedation and recovery sleep with a chemical, an effect highly comparable to recovery sleep was produced.
After this study, the researchers are planning to continue investigating mechanisms in the brain when sleep is induced, gaining a better understanding of how the brain responds to being tired.
The study received funding support from the ERASMUS Program, the UK-China Scholarships for Excellence Scheme, the Wellcome Trust, the Biotechnology and Biological Sciences Research Council and the Medical Research Council.
Nicholas Franks, Zhe Zhang, Edward Hardin, Valentina Ferretti, Zoe Pillidge, Ilke Guntan, Raquel Yustos, Alessandro Moro, Stephen Brickley, Eleonora Steinberg, Alexei Vyssotski, Zhiwen Ye, Xiao Yu and Anna Zecharia also participated in the study.
