Contact:
Jeremy Craig, 404-413-1357
University Relations
ATLANTA — Georgia State University neuroscientists have found that there are differences between male and female hormonal and behavioral responses to physical abuse early in life – an insight that might one day lead to gender-specific treatments for mood disorders.
The team of Bradley Cooke, assistant professor at GSU’s Neuroscience Institute, and graduate students Jill M. Weathington and Amanda R. Arnold explored the subject by exposing young male and female rats to aggressive acts by adult male rats.
When the rats grew into adulthood, the scientists found that the female rats were more severely affected by the experience, showing both behavioral changes as well as lasting hormonal changes as a result. The findings will appear in an upcoming edition of the journal Hormones and Behavior.
The rats were tested behaviorally through using a swim test, an elevated ‘plus’ maze, and a social interaction test. In the swim test, females were more likely to stop swimming sooner than the males, reflecting a greater tendency to depression among the abused females.
“It was a very striking effect,” Cooke said. “In terms of the swim test, it seemed to be completely absent in males and very strong in females. There also appears to be a dysregulation, perhaps a permanent one, in the stress response system, and we’re interested in how that takes place.”
The findings are important in expanding scientists’ understanding of how abuse during childhood may affect the development of mood disorders later in life. Child abuse and neglect are major risk factors for depression and anxiety. Women are twice as likely as men to suffer from depression, according to statistics.
The results from Cooke’s team, which found that abused females had very high stress hormone responses, have also been observed in humans, with women showing the same pattern.
The lab is continuing to work on trying to understand whether males and females process experiences in different ways. One of the things they’re looking at is a receptor for a neurotransmitter, called the CRF receptor, which is involved in processing experiences of abuse.
“It appears to be more intensely expressed in males than in females, and this is a clue that there could be a sex difference in CRF receptor signaling,” Cooke said. “Hopefully, this will allow us to study how males and females respond to drugs that target this receptor.”
The article, which is in press, is Weathington, J.M., et al., Juvenile social subjugation induces a sex-specific pattern of anxiety and depression-like behaviors in adult rats, Horm. Behav. (2011), doi:10.1016/j.yhbeh.2011.10.008.
NOTE: Members of the media interested in the article may contact Jeremy Craig, 404-413-1357 or jcraig@gsu.edu to obtain a copy in PDF format.
Dec. 9, 2011