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 Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH

nachricht Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>