Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Progesterone regulates male behavior toward infants

25.02.2003


In an unexpected discovery, a team led by Northwestern University scientists has become the first to show that progesterone, a hormone usually associated with female reproduction and maternal behavior, plays a key role in regulating male aggression toward infants in mice. Testosterone, not progesterone, had been thought to be responsible.



The researchers found that the absence of progesterone’s actions reduced aggression while promoting positive paternal behavior. The findings, to be published online by the Proceedings of the National Academy of Sciences during the week of Feb. 24, suggest a new approach to studying an area of biology that has been poorly understood.

"We discovered that the hormone progesterone and its receptor are important in males, not just females," said Jon E. Levine, professor of neurobiology and physiology, who led the provocative study. "Paternal behavior may be based in the same biology as maternal behavior."


Like adult males of many other species, male mice rarely contribute to parental care and often attack or kill infants soon after birth. Although this hostile behavior had previously been attributed to testosterone, a correlation between testosterone and male behaviors directed at young has never been established. Seeking another explanation for the male behavior, Levine’s research team tested paternal behavior in progesterone receptor knockout mice. (These mice lack the gene that encodes progesterone receptors and thus the animals are not affected by the presence of progesterone.)

"In male knockout mice we noticed something quite startling," said Levine. "They behaved differently, and the most obvious changes were a complete lack of aggression toward infants and the emergence of active paternal care. These animals are terrific dads."

After breeding males of both the knockout and a control strain, the researchers found a complete absence of infanticide in the resulting litters born to knockout mice. Comparatively, 74 percent of the control mice committed infanticide. Additionally, knockout mice contributed significantly more paternal care than the controls by frequently contacting pups and retrieving them to nests.

In a separate experiment, the researchers used a drug to block the progesterone receptors in normal mice and found that these mice behaved like the knockout mice -- they were highly paternal.

Because, like the controls, the knockouts exhibited similar levels of aggression toward other adult males, the researchers surmised that the knockouts’ general level of aggression, a testosterone-dependent behavior, is not affected in these animals. These results suggest that progesterone, and not testosterone, may be key in specifically controlling infant-directed aggression in male mice.

"The same neuroendocrine mechanism may be important in other mammals, including humans, but further research is required," said Levine. "At least in the case of mice, this appears to be an important neurochemical switch that can increase paternal behavior and decrease aggressive behavior toward infants."

Other authors on the paper are Johanna S. Schneider (lead author), Marielle K. Stone and Teresa H. Horton, from Northwestern University; Katherine E. Wynne-Edwards, from Queens University, Kingston, Ontario; and John Lydon and Bert O’Malley, from Baylor College of Medicine, Houston.

The research was supported by the National Institute of Child Health and Human Development.

Megan Fellman | EurekAlert!
Further information:
http://www.nwu.edu/

More articles from Life Sciences:

nachricht A novel socio-ecological approach helps identifying suitable wolf habitats
17.02.2017 | Universität Zürich

nachricht New, ultra-flexible probes form reliable, scar-free integration with the brain
16.02.2017 | University of Texas at Austin

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Biocompatible 3-D tracking system has potential to improve robot-assisted surgery

17.02.2017 | Medical Engineering

Real-time MRI analysis powered by supercomputers

17.02.2017 | Medical Engineering

Antibiotic effective against drug-resistant bacteria in pediatric skin infections

17.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>