The absence of a key signaling protein in the brain during infancy could lead to anxiety disorders later in life, scientists say. According to findings published today in the journal Nature, mice lacking the receptor protein for the chemical messenger serotonin just after birth exhibit abnormal anxiety as adults.
Researchers have known for some time that mice genetically engineered to lack the receptor for serotonin, a neurotransmitter, show anxiety-like behavior. But the new results go one step further, revealing when in life and where in the brain the link between serotonin receptors and anxiety behavior is forged. As in earlier studies, the investigators, led by René Hen of Columbia University, first created a line of so-called knockout mice that lacked the gene encoding the receptor protein. Those mice showed the expected signs of anxiety, such as moving around less open spaces and taking longer to start eating in new environments as compared with normal animals. To determine which of the two receptor populations--the one in the forebrain or the one in the brainstem--is most critical in that regard, the team then crossed the knockout mice with a line engineered to activate receptor expression in particular brain regions. The resulting line of double-transgenic "rescue" animals expressed the serotonin receptors only in the forebrain, but exhibited normal anxiety behavior. Further tests, in which the drug doxycycline was used to suppress the receptors in mice at various stages of development, showed that eliminating the receptors in juvenile or adult mice did not elicit over-anxiousness.
"Forebrain serotonin receptors are needed during the development of newborns to modulate the predisposition to anxiety-like behavior, but are no longer critical during adult life," Solomon Snyder of Johns Hopkins University explains in a commentary accompanying the report. He proposes that variations in serotonin-sensitive neurons and serotonin receptors early in life might account for the importance of maternal nurturing in preventing emotional disorders later in life. Rats that were not groomed sufficiently as pups by their mothers display elevated levels of anxiety as adults, he notes. "Assuming that we can equate developmental stages in mice and humans," Snyder reflects, "these findings might be relevant to brain development and the genesis of anxiety in people too."
Kate Wong | Scientific American
Research team creates new possibilities for medicine and materials sciences
22.01.2018 | Humboldt-Universität zu Berlin
Saarland University bioinformaticians compute gene sequences inherited from each parent
22.01.2018 | Universität des Saarlandes
On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.
We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
22.01.2018 | Materials Sciences
22.01.2018 | Earth Sciences
22.01.2018 | Life Sciences