By Mallory Creveling AOL Health
Science may explain why more women suffer from depression and other stress-related disorders than men.
In an animal study published in Molecular Psychiatry, neuroscience researchers found that women are more sensitive to a certain stress hormone and less able to adjust to high levels of the hormone than men.
Many scientists recognize that women have a higher rate of depression, post-traumatic stress disorder and anxiety disorders, so Rita J. Valentino, a behavioral neuroscientist at The Children’s Hospital of Philadelphia, and her colleagues studied the biological mechanisms behind this gender difference.
Focusing on the stress hormone that manages stress responses in mammals, known as the corticotrophin-releasing factor or CRF, researchers analyzed the brains of rats in response to a swim stress test.
The findings revealed that the female rats’ neurons had receptors for CRF that bound more tightly to cell-signaling proteins than the male rats. This made the females more sensitive to CRF.
The researchers also found that the male rats had an adaptive response to CRF in their brain cells, which reduced their number of CRF receptors, making them less responsive to the hormone. This did not occur in the females.
“This is the first evidence for sex differences in how neurotransmitter receptors traffic signals,” Valentino said in a statement. “Although more research is certainly necessary to determine whether this translates to humans, this may help to explain why women are twice as vulnerable as men to stress-related disorders.”
Valentino said that previous animal studies on stress disorders focused solely on males, which is why these gender differences may have been overlooked. And while this biological mechanism in rats may not be the same in humans (because other mechanisms play a role in human stress responses) scientists recognize that stress-related psychiatric disorders interrupt CRF regulation. Therefore, these findings are most likely relevant to humans.
Understanding sex differences in stress disorders is important for treatments, Valentino added.
“Pharmacology researchers investigating CRF antagonists as drug treatments for depression may need to take into account gender differences at the molecular level,” she added.
