New research from the University of Cincinnati (UC) shows that elevated levels of sodium blunt the body's natural responses to stress by inhibiting stress hormones that would otherwise be activated in stressful situations. These hormones are located along the hypothalamic-pituitary-adrenal (HPA) axis, which controls reactions to stress.
The research is reported in the April 6, 2011, issue of The Journal of Neuroscience, the official journal of the Society for Neuroscience.
"We're calling this the Watering Hole Effect," says Eric Krause, PhD, a research assistant professor in the basic science division of UC's department of psychiatry and behavioral neuroscience and first author of the study. "When you're thirsty, you have to overcome some amount of fear and anxiety to approach a communal water source. And you want to facilitate those interactions—that way everyone can get to the water source."
Krause and his team dehydrated laboratory rats by giving them sodium chloride, then exposed them to stress. Compared with a control group, the rats that received the sodium chloride secreted fewer stress hormones and also displayed a reduced cardiovascular response to stress.
"Their blood pressure and heart rate did not go up as much in response to stress as the control group's, and they returned to resting levels more quickly," says Krause.
"Also, in a social interaction paradigm with two rats interacting, we found them to be more interactive and less socially anxious."
Further research, through examination of brain and blood samples from the rats, showed that the same hormones that act on kidneys to compensate for dehydration also act on the brain to regulate responsiveness to stressors and social anxiety.
The elevated sodium level, known as hypernatremia, limited stress responses by suppressing the release of the pro-stress hormone angiotensin II. Conversely, it increased the activity of oxytocin, an anti-stress hormone.
Further research, Krause says, will examine these hormones and neurocircuits to investigate their role in social anxiety disorders and autism, a neurological disorder whose characteristics include social impairment.
"Oxytocin deficiency has been implicated in autism in previous studies," says Krause. "We'd like to investigate the possibility that dysregulation in fluid balance during pregnancy could result in autistic disorders."
Krause's team also included Annette de Kloet, Jonathan Flak, Michael Smeltzer, Matia Solomon, Nathan Evanson, Stephen Woods, Randall Sakai and James Herman.
The research was funded by grants from the National Institutes of Health and the American Heart Association. The authors declare no competing financial interests.
Keith Herrell | EurekAlert!
Using fragment-based approaches to discover new antibiotics
21.06.2018 | SLAS (Society for Laboratory Automation and Screening)
Scientists learn more about how gene linked to autism affects brain
19.06.2018 | Cincinnati Children's Hospital Medical Center
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
22.06.2018 | Materials Sciences
22.06.2018 | Earth Sciences
22.06.2018 | Life Sciences