The study on hamsters, which advances basic knowledge on the connection between certain sex hormones and aggression, could go on to advance research on the treatment of inappropriate aggression in humans, researchers said.
"The results show for the first time that melatonin acts directly on the adrenal glands in females to trigger a'seasonal aggression switch' from hormones in the gonads to hormones in the adrenal glands - a major contrast to how this mechanism works in males," said lead author Nikki Rendon, a PhD student at Indiana University in US.
The new study shows that melatonin acts directly on the adrenal glands in females to trigger the release of DHEA. DHEA can be converted to androgens and estrogens, which affect aggression in both males and females. In females, DHEA appears to compensate for low levels of estradiol - a form of estrogen - that occurs during the winter.
The research was conducted in Siberian hamsters, or Phodopus sungorus, a species with a similar adrenal system to humans. Collectively, the results show that melatonin is the primary regulator of aggression in females.
"It's growing increasingly clear that sex hormones play an important role in controlling aggression in both males and females - but females, human and non-human, are traditionally vastly understudied in the sciences," Rendon said.
"By conducting this research on females, we are increasing our understanding of hormones and social behaviour in a field currently dominated by discussions on testosterone regulating aggression in males," she said.
The study was published in the Proceedings of the Royal Academy B.


Latest News from Lifestyle News Desk