UW researchers' discovery sheds light on reproductive hormones

The Capital Times  —  1/11/2009 11:01 am

University of Wisconsin-Madison researchers have solved a mystery surrounding a "rogue protein" that plays a role in the release of neurotransmitters and hormones in the brain.

The scientists found abundant amounts of the puzzling protein -- whose main location and function were unknown -- in a specific area of the pituitary gland. Like someone at a control knob, the protein may adjust the release of two hormones -- oxytocin, which controls many reproductive functions, and vasopressin, which controls fluid balance.

This ability to modulate hormone release may have important implications for pregnancy, birth, lactation and the menstrual cycle, the researchers said.

For example, early release of oxytocin can lead to premature birth.

The study appears in the Jan. 11 issue of Nature Neuroscience.

"The findings raise very interesting possibilities for women's health, in which rising and falling hormone levels play a key role in many biological processes," said senior author Meyer Jackson, a professor of physiology at the UW-Madison School of Medicine and Public Health. But more studies will be needed to better understand the protein, he added.

Jackson teamed with Edwin Chapman, a Howard Hughes Medical Institute investigator and a fellow School of Medicine and Public Health physiology professor.

The researchers conducted high-powered biophysical measurements to compare the pituitaries of normal mice and those in which a triggering protein had been knocked out.

They found that the protein determined whether an electrical impulse will let a large or small amount of hormone out of the nerve terminal.

The Capital Times  —  1/11/2009 11:01 am