How does melatonin promote sleep? Scientists look to worms for answers

play article
Subscribers can listen to this article
  • Melatonin promotes sleep in humans, yet it is not understood exactly how this happens
  • Sleep in worms is similar to sleep in humans
  • Scientist, therefore, used roundworms to reveal how melatonin works in the brain

Melatonin is a hormone produced in the brain that regulates our natural sleep-wake cycle, and it is produced in response to darkness.

It is also used as a dietary supplement to help treat conditions like delayed sleep-wake phase disorder (DSWPD) and jet lag. Until recently, it was not understood exactly how melatonin works in the human brain.

What was known is that in order to promote sleep, melatonin has to link with melatonin receptors in the brain. In the human brain, these two receptors are known as MT1 and MT2. Researchers, however, did not know exactly what happens once melatonin links with these receptors.

Do worms sleep?

Interestingly, worms do sleep, and researchers noted that sleep is quite similar in worms, humans and mice. Neuroscientists from the University of Connecticut School of Medicine used C. elegans worms (also known as roundworms) to study this phenomenon. 

The found that when melatonin binds with the MT1 receptor it opens a potassium channel, known as the BK channel, that is responsible for limiting the release of neurotransmitters.

No receptor means less sleep

Put simply, when neurotransmitter release is inhibited, sleep is promoted. However, in order for the BK channel to limit neurotransmitter release, a melatonin receptor is necessary.

As a result, the researchers found that melatonin promoted sleep in worms by stimulating the BK channel through the melatonin receptor. When worms did not produce melatonin, lacked melatonin receptors or the BK channel, they spent less time sleeping. 

How does this benefit humans?

Because sleep is similar in worms and humans, these findings helped researchers understand how melatonin works in the human brain – which may lead to ways to alleviate sleep-related conditions.  

Image credit:

We live in a world where facts and fiction get blurred
In times of uncertainty you need journalism you can trust. For 14 free days, you can have access to a world of in-depth analyses, investigative journalism, top opinions and a range of features. Journalism strengthens democracy. Invest in the future today. Thereafter you will be billed R75 per month. You can cancel anytime and if you cancel within 14 days you won't be billed. 
Subscribe to News24
Voting Booth
Zama zama crackdown: What are your thoughts on West Village residents taking the law into their own hands?
Please select an option Oops! Something went wrong, please try again later.
Authorities should bring in the army already
11% - 1179 votes
Illegal miners can't be scapegoated for all crime
49% - 5352 votes
What else did we expect without no proper policing
37% - 4080 votes
Vigilante groups are also part of the problem
4% - 389 votes
Rand - Dollar
Rand - Pound
Rand - Euro
Rand - Aus dollar
Rand - Yen
Brent Crude
Top 40
All Share
Resource 10
Industrial 25
Financial 15
All JSE data delayed by at least 15 minutes Iress logo
Editorial feedback and complaints

Contact the public editor with feedback for our journalists, complaints, queries or suggestions about articles on News24.