Corporate Banner
Satellite Banner
ADME Tox
Scientific Community
 
Become a Member | Sign in
Home>News>This Article
  News
Return

Mice and Rats Stressed by Male Experimenters

Published: Thursday, May 01, 2014
Last Updated: Thursday, May 01, 2014
Bookmark and Share
An international team of pain researchers led by scientists at McGill University have found that the gender of the experimenters has a big impact on the stress levels of rodents.

In research published online April 28 in Nature Methods, the scientists report that the presence of male experimenters produced a stress response in mice and rats  equivalent to that caused by restraining the rodents for 15 minutes in a tube or forcing them to swim for three minutes. This stress-induced reaction made mice and rats of both sexes less sensitive to pain.

Female experimenters produced no such effects.

“Scientists whisper to each other at conferences that their rodent research subjects appear to be aware of their presence, and that this might affect the results of experiments, but this has never been directly demonstrated until now,” says Jeffrey Mogil, a psychology professor at McGill and senior author of the paper.

The research team, which included pain experts from Haverford College and the Karolinska Institutet in Sweden and a chemosensory expert from Université de Montreal, found that the effect of male experimenters on the rodents’ stress levels was due to smell. This was shown by placing cotton T shirts, worn the previous night by male or female experimenters, alongside the mice; the effects were identical to those caused by the presence of the experimenters, themselves.

Further experiments proved that the effects were caused by chemosignals, or pheromones, that men secrete from the armpit at higher concentrations than women. These chemosignals signal to rodents the presence of nearby male animals. (All mammals share the same chemosignals).

These effects are not limited to pain. The researchers found that other behavioural assays sensitive to stress were affected by male but not female experimenters or T-shirts.

“Our findings suggest that one major reason for lack of replication of animal studies is the gender of the experimenter – a factor that’s not currently stated in the methods sections of published papers,” says Robert Sorge, a psychology professor at the University of Alabama, Birmingham. Sorge led the study as a postdoctoral fellow at McGill.

The good news, Mogil says, is that “the problem is easily solved by simple changes to experimental procedures. For example, since the effect of males’ presence diminishes over time, the male experimenter can stay in the room with the animals before starting testing.  At the very least, published papers should state the gender of the experimenter who performed the behavioral testing.” 

The work was supported by grants from the Louise and Alan Edwards Foundation, the Natural Sciences and Engineering Research Council of Canada and the U.S. National Science Foundation.

 “Olfactory exposure to males, including men, causes stress and related analgesia in rodents”, Robert E. Sorge, et al.


Further Information

Join For Free

Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 3,000+ scientific posters on ePosters
  • More than 4,400+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

His and Hers Pain Circuitry in the Spinal Cord
New animal research reveals fundamental sex differences in how pain is processed.
Monday, July 06, 2015
Scientific News
Cell Transplant Treats Parkinson’s in Mice
A University of Wisconsin—Madison neuroscientist has inserted a genetic switch into nerve cells so a patient can alter their activity by taking designer drugs that would not affect any other cell.
Understanding Female HIV Transmission
Glowing virus maps points of entry through entire female reproductive tract for first time.
Experimental Drug Cancels Effect from Key Intellectual Disability Gene
A University of Wisconsin—Madison researcher who studies the most common genetic intellectual disability has used an experimental drug to reverse — in mice — damage from the mutation that causes the syndrome.
Common Class of Cancer Drugs May Not Lead to Cognitive Decline
UCLA study refutes 2015 research suggesting anthracyclines could cause memory loss, other impairments.
Designing Better Drugs
A rational drug engineering approach could breathe new life into drug development.
Genetic Approach May Lead to New Treatments for Digestive Diseases
Researchers at UMass Medical School have identified a new molecular pathway critical for maintaining the smooth muscle tone that allows the passage of materials through the digestive system.
Potential Target for Revolutionary Antibiotics
An international team of including the Lomonosov Moscow State University researchers discovered which enzyme enables Escherichia coli bacterium (E. coli) to breathe.
Unique Model for Studying ALS
Unique mouse model will allow researchers to better study the genetic origins and potential treatments of ALS.
Factors Influencing Influenza Vaccine Effectiveness Uncovered
The long-held approach to predicting seasonal influenza vaccine effectiveness may need to be revisited, new research suggests.
New Model to Enhance Zika Virus Research
The model will allow researchers to better understand how the virus causes disease and aid in the development of antiviral compounds and vaccines.
SELECTBIO

SELECTBIO Market Reports
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
3,000+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,400+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FOR FREE!