At what rate are nerve cells restored?
Nuclear tests helped to measure the rate of formation of new neurons
The researchers' work has been published in the journal Cell, ScienceNOW (Atomic Bombs Help Solve Brain Mystery) writes briefly about it.
Figure from the article in Cell Dynamics of Hippocampal Neurogenesis in Adult Humans – VM.
A group led by Kirsty Spalding, an employee of the Swedish Karolinska Institute, isolated neurons from the nervous tissue of people who bequeathed their brains for research. Individual tissue cells were labeled with fluorescent dyes and passed through a so–called sorter - a device that separates cells of different types based on the color of the attached markers. Having thus separated neurons from auxiliary glial cells (their ability to divide has long been known), scientists isolated DNA from the first and measured the content of the carbon-14 isotope in it.
The concentration of this isotope in the Earth's atmosphere first rose sharply during the first open nuclear tests, and then, after the ban imposed in 1964, began to fall. Therefore, knowing the content of 14C in the DNA of neurons, scientists could date the time of its synthesis and, accordingly, determine the rate of appearance of new neurons in the adult brain.
Neuroscientists have found that an adult has about 1,400 neurons per day in the hippocampus, a part of the brain associated with emotions and memory formation. In old age, the rate of neurogenesis decreases slightly.
The new experiment of Spelding and her co-authors is important for neuroscience, because previously conducted experiments on the study of neurogenesis in mice gave difficult to interpret results. In mice, new neurons were formed most actively in the olfactory bulbs, although a year ago the same group showed that there were practically no new neurons in humans in the corresponding department.
Portal "Eternal youth" http://vechnayamolodost.ru07.06.2013