Researchers from Johns Hopkins identified a type of neuron in the brains of mice. That appears to play a central role in promoting sleep by Shutting off wake up neurons.
The newly identified brain cells, located in a part of the hypothalamus called the zona Incerta. They prefer to offer drug in treating sleep disorders. As insomnia and narcolepsy, caused by the dysfunction of sleep-regulating neurons.
The Hypothalamus is an ancient system that was relatively well-conserved in evolution from fish to humans, understanding its genetics and chemistry in mice should advance our knowledge of what happens in people’s brains, says Seth Blackshaw, Ph.D., professor of neuroscience at the Johns Hopkins University School of Medicine, the study’s lead author.
Neurons that exhibit gene called Lhx6. Lhx6-expressing cells have not observed in this area of the brain before and appear to connect the zona Incerta Areas of the brain that control sleep and wakefulness.
Lhx6 is a gene that is essential for the formation of neurons that inhibit other neurons. The brain use Lhx6 and gene is important these areas to develop properly. The known function of this gene in other cells. Researchers to study whether the Lhx6-expressing neurons played a role in inhibiting wake-promoting neurons.
To test the role of the Lhx6-expressing neurons in regulating these parts of sleep, the researchers used artificial receptors called designer receptors activated by designer drugs to increase the activity of neurons in mice and observed their behavior. However, researchers observed an increase in both REM and non-REM sleep for eight hours When neuron activated following treatment.
One population of cells connected to the Lhx6-expressing cells are neurons that are known to secrete hypocretin. A signal that promotes and sustains wakefulness, and which is disrupted in narcolepsy.
Using drugs that block hypocretin action, the researchers explained that the increase in non-REM sleep activation of Lhx6-expressing cells dependent on hypocretin. But that the increase in REM sleep was not. Moreover, the Lhx6 inhibits only hypocretin-producing cells. But also other types of wake-promoting cells, says the study’s first author, Kai Liu, a graduate student in the Solomon H. Snyder Department of Neuroscience at the Johns Hopkins University School of Medicine.
Furthermore, test Lhx6-expressing cells influence on these wake-promoting neurons.n Disrupted both their formation and inhibited their activity. Although, obtaining a similar result by activity of these neurons provides stronger evidence that Lhx6 cells are necessary for control of sleep says Liu.