When you get thirsty, there is a buzz of new water immediately supporting. But bless some of the quiet sea water and you still feel wrapped.
That's because your brain tries to keep the salt density in your body within a very narrow range, saying Zachary Knight, professor of linguistics at the University of California, San Francisco and California. researcher with Howard Hughes Medical Institute.
"If, for example, you get a change of 10%, you would be very miserable," he said. "20% changed and you could die."
Knight and a team of researchers wanted to find out how the brain keeps fitting. They recite the results of their research in an article published each Wednesday in the magazine Nature.
"There needs to be a rationale for the brain to look at how you solve the solutions and you use that to be dry," said Knight. "But the engine wasn't unknown."
Knight's team like that started to examine brain cells called thirsty neurons.
At first, the crew gave some water in a stomach.
"Within a few minutes, flowing water runs into the stomach quickly turning this thirsty neurons in the brain," said Chris Zimmerman, a graduate of Knight's fieldwork who carried out the experiment. "And that's not only," said Zimmerman, "if we give it [the mouse] it doesn't get water. "
Then repeat the test team, using salted water. And this time the neurons stayed thirsty and their animals looked for freshwater that would lower their salt content in their bodies.
More research showed how the system works. Cells in the gut always measure luxury and communicate that information to thirsty neurons in the brain.
“Not only are we fascinating to find out this new feature from the gesture to the brain, but also that we have found that we have a special responsibility in terms of control. "Zimmerman said," he said, "to keep us moving," said Zimmerman.
Second inspection Nature a look at another system which will also affect the inclusion of salt.
“We wanted to know how the brain regulates the sodium appetite,” said Yuki Oka, a professor of biology at Caltech and the author of the study.
The first thing that the Oka team did was to use a technique called optogenetics to turn the sodium appetite neurons.
The effect on mice was immediate. "They pick up a piece of rock salt and then start eating," said Oka.
When the crew removed the sodium appetite, the animals stopped eating salt.
But how does this system work when there is no expert listening to the change?
Earlier research has shown that part of the answer involves cells that measure salt collections in the bloodstream.
But the Oka team were making sure it wasn't the whole answer as animals only need a small amount of sodium in their diet. So they have to stop eating salt long before the blood pressure starts to rise.
The scientists thought that the second “flame” was to be done somewhere – one that could go faster.
He was found in the rhythms of the animals.
“When you put sodium on the top of your speech, and then when you grow it, that's enough to suppress sodium appetite neurons,” said Oka. That's how we know to stop eating salt before we build up a harmful dose.
And sports drinks, the UCSF scientists explain, give the same sodium levels found in our bodies; that's how the drinks replace sodium without making a response to the "first stop of salt" in the brain.