login
Become a member
Quick Registration
Full Registration Benefits -
Free Homepages for Doctors
Free Homepages for Hospitals
Free Homepages for Medical Conference
Free Homepages for NGO's
Personal Health Record Creation
Access to all Medical Slides
Access to all Jobs & Products Sale
Clues in Age-related Human Diseases Provided by Cell Death in Sparrow Brains
September 18, 2007 at 5:50 PM
Senior Health News
Writing in today’s Proceedings of the National Academy of Sciences, researchers from the University of Washington and the University of California, Berkeley, report a striking shrinkage in the size of the brain regions that control singing behavior of Gambel’s white-crowned sparrows. This transformation is triggered by the withdrawal of testosterone, a naturally occurring steroid hormone, and is apparent within 12 hours. The study is the first to report such rapid regression of brain nuclei caused by the withdrawal of a hormone and a change in daylight conditions in adult animals.
“The changes are substantial,” said Christopher Thompson, lead author of the study and a UW doctoral student in neurobiology and behavior. “First, the volume of a song-control region called the HVC collapses 12 hours after testosterone is removed from circulation. Then, by four days, thousands of HVC neurons are lost. We have good reason to believe that they are killed by a cell suicide program call apoptosis.”
Co-authors of the study are Eliot Brenowitz, a UW professor of psychology and biology, and George Bentley, a former UW postdoctoral researcher who is now a UC Berkeley assistant professor of integrative biology.
The research mimicked the natural seasonal changes that occur in the brains of the sparrows. Their song-control regions expand in the spring and summer leading up to the breeding season, as they use songs to establish territories and attract mates in Alaska. Later in the summer, as the birds get ready to migrate back to California, the same brain regions shrink.
|
|
|
 Comment & Contribute
|
- Health News Index
|
|
- News Quick Links
 |
Brain
Complete Medindia Resources
|
| News Categories: |
| » | Gasoigne Swaps Booze for Botox |
| » | Michelle Obama: Name of Olive Tree in Italy |
| » | Beyonce: Most Beautiful Women in the World |
| » | Robin Gibb Recovers from Coma Wakes Up to Cancer |
| » | Botox and Vitamin Jabs Maintain Simon Cowell’s Young Looks |
| More Celebrity News | |
|
