In the new study, researchers from the German Aerospace Center have studied the molecular changes that occur in the human brain during the long phases of wakefulness. The subjects did not sleep for 52 hours and then scanned their brains. After that, the participants moved to Cologne, where under the supervision of scientists they slept 14 hours.
Lack of sleep seriously affects the performance, health, and changes in the brain. "Studies have shown that lack of sleep increases the number of available A1-adenosine receptor. Due to the subsequent phase of sleep, they returned to the original level, "- said Dr. David Elmenhorst from the Institute of Neurology.
A1 adenosine receptors embedded in the cell wall. Their function consists of sending a signal from adenosine into the interior of cells. Not only adenosine A1 receptors but also responsible for the need for sleep, which becomes stronger in the absence of sleep. Adenosine is an elementary product of energy metabolism.
The effect of caffeine is also associated with this type of receptor. Stimulator accumulated in complex protein molecules and blocked. In this series of experiments, the subjects had to do without coffee and other invigorating substances. During the 52-hour phase, they were subjected to several tests to determine the memory capacity. One of the features - individual differences in memory: some participants, sleep-deprived, could not recall the information, but on the other is not affected. These findings are of interest for the jobs where people need to act, despite the lack of sleep.
"We did not measure the constant value A1 receptor density in the group of subjects", - said David Elmenhorst. Indicator molecules in the flow of blood test are fixed on the free receptor molecules and can occur in the PET scanner, including during disintegration. Thus, register only those receptors that are not blocked and, therefore, are available during the measurement. "The theory is that subjects with high density A1 adenosine receptors and produce little inhibit cell activity to a lesser extent", - said Elmenhorst.
The results are relevant to clinical medicine: deprivation (deprivation) sleep - a method of treating depression, but it is effective only for a short time. "Scientists are taking steps to increase the duration of the therapeutic effect of sleep deprivation in the treatment of depression, but the problem is that when people are returning to the usual regime, depression and back," - says David Elmenhorst. Understanding the relationship between mood and regulation of adenosine help optimize therapeutic procedures.