Sam Wong in MedicalXpress:
Researchers have gained fresh insights into how 'local' body clocks control waking and sleeping. All animals, from ants to humans, have internal 'circadian' clocks that respond to changes in light and tell the body to rest and go to sleep, or wake up and become active. A master clock found in part of the brain called the suprachiasmatic nucleus (SCN) is thought to synchronise lots of 'local' clocks that regulate many aspects of our metabolism, for example in the liver. But until now scientists have not had sufficient evidence to demonstrate the existence of these local clocks in the brain or how they operate. In a new study looking at mice, researchers including Professors Bill Wisden and Nick Franks at Imperial College London and Dr Mick Hastings' group at the MRC Laboratory of Molecular Biology in Cambridge have investigated a local clock found in another part of the brain, outside the SCN, known as the tuberomamillary nucleus (TMN). This is made up of histaminergic neurons, which are inactive during sleep, but release a compound called histamine during waking hours, which awakens the body.
…Senior researcher Professor Bill Wisden from the Department of Life Sciences at Imperial College London said: “Getting enough good quality sleep is crucial – it helps keep us mentally and physically healthy, as well as being a key factor in having a good quality of life. A lot of people would love to have more a concentrated and restful night's sleep, but at the moment we still don't know enough about exactly why we fall and stay asleep. Our work with mice suggests that local body clocks play a key role in ensuring their sleeping and waking processes work properly. When a local clock was disrupted, their whole sleep and wake system malfunctioned. Ultimately, understanding local clocks better might enable us to target them to help people have a better night's sleep.”
More here.