tiny molecule cause of depression tiny molecule cause of depression Researchers are studying seasonal affective disorder. (Photo: Evgeny Atamanenko/Shutterstock)

How a gerbil could save you from depression this winter

They're cute and furry, and these rodents are also being used in some pretty eye-opening discoveries about seasonal affective disorder (SAD).

Now that daylight saving time has ended, we've officially bid summer farewell and begun preparing for the inevitable: shorter days, bitter cold, pre-holiday frenzy, post-holiday letdown. It can be a cruel set of circumstances for even the strongest among us. It can make us feel ... well, depressed. And it even has an official medical diagnosis: seasonal affective disorder, or SAD. (We know, awww.)

Scientists have been studying this condition for years and have devised some pretty promising treatment options that bring hope to the 4-6 percent of people around the country who suffer from it. But there's one thing that's thrown a wrench in the research thus far: Using traditional lab rats just isn't cutting it. They don't produce melatonin like humans do, for one. And they're nocturnal, unlike humans, who are diurnal.

So a few years ago, a pair of Israeli researchers from Tel Aviv University and the University of Minnesota decided to search for a new test subject whose characteristics are more like humans. And they found it ... in a type of gerbil called the fat sand rat.

The fat sand rat is in the gerbil family and is an inhabitant of Israel's desert regions.The fat sand rat is in the gerbil family and is an inhabitant of Israel and nearby countries. (Photo: Wikimedia Commons)

By using the fat sand rat (which doesn't look nearly as fat as we thought) in the lab, the researchers think they've found a breakthrough in the study of SAD and similar mood disorders.

To test their theory, Professors Noga Kronfeld-Schor of Tel Aviv University's Department of Zoology and Haim Einat of the University of Minnesota examined how the rats reacted to different levels of light exposure. As they predicted, the rats had a similar response to humans. From there, they tested common medications and therapies used to treat SAD in humans and found, again, that their reactions were similar.

"Humans have been using this treatment for a long time," said Kronfeld-Schor, referring to light exposure therapy. "But many of us thought that a large part of its success was based on the placebo effect. For the first time, we've found it to be effective in animals as well, which weakens the possibility of the placebo effect."

This improved animal model will "advance understanding of the disorder, help screen for effective treatments and allow for the development of new therapies," the researchers said.


Photos and SlideshowsPhotos and Slideshows

Related Topics: Science