In a study at the University of Illinois, recently published in the Journal of Applied Physiology, exercise-trained mice developed far fewer gallstones than mice who didn't exercise. "For the first time, we have direct evidence that physical activity reduces gallstone formation, adding to the ever-increasing number of reasons that people should get more exercise," said Kenneth Wilund, assistant professor in kinesiology and community health. In the study, 50 gallstone-susceptible mice ate a high-fat diet with cholic acid, which aids in absorbing cholesterol. (Gallstones form because bile ... Read More

In an experiment conducted with a group of six degus (cousins of the guinea pig), scientists placed sunflower seeds just out of the rodents' reach on the other side of a Lilliputian picket fence but provided the animals with tiny rakes. By the conclusion of the 60-day study period, all the degus had figured out how to pull the seeds within reach by using the miniature garden implement. Can a TV development deal for a rodent version of Home Improvement be far behind? Video: Rodents using tools ... Read More

However, the lack of an animal model for bipolar disorder has been a major obstacle to developing better treatments for the disease. Now, researchers at the National Institute of Health, writing in Molecular Psychiatry, report promising results from an experiment with mice that had been bred with a specific gene defect associated with bipolar disorder. (Unlike some brain diseases, no single gene has been identified as the cause of bipolar disorder, which scientists believe results from a combination of environmental and genetic factors.) The genetically engineered mice, missing the GluR6 gene, ... Read More

Mice, unlike men, do not spontaneously develop kidney stones, which has thus far prevented scientists from establishing an animal model to investigate the painful disease. However, a new study by Jeffrey S. Clark in the Journal of Physiology has pinpointed some of the differences between mice and men, and could lead the way to the development of a mouse model to aid in kidney stone research. About three in 20 men (and one in 20 women) in developed countries get kidney stones at some point in their life. Kidney stones are solid deposits of various minerals, particularly oxalate, that should be ... Read More

Writing in the April issue of the journal Anesthesiology, researchers from Massachusetts General Hospital report that low doses of hydrogen sulfide can safely and reversibly lower metabolism and certain cardiovascular functions in mice. And the effects — including a big decrease in heart rate without a drop in blood pressure — don't require a reduction in body temperature. "Hydrogen sulfide is the stinky gas that can kill workers who encounter it in sewers; but when adminstered to mice in small, controlled doses, within minutes it produces what appears to be totally reversible ... Read More

In a study at the University of Cagliari, researchers tested whether administering GHB decreases alcohol cravings in specially bred Sardinian alcohol-preferring rats. The rats were trained to press a lever when they wanted a drink, under a program of "operant, oral alcohol self-administration" (i.e., bellying up to the bar). Once the rats had established their tolerance levels and drinking patterns, they were divided up into two groups to test for the effect of GHB on alcohol's motivational strength. (Two control groups of rats drank sucrose instead.) The experiments showed that doses of GHB ... Read More

For years, scientists have been studying cystic fibrosis, one of the most common and deadly genetic diseases, using gene-altered mice. But there had always been a catch: Cystic fibrosis, which is incurable, attacks mainly the lungs and digestive system, and lung failure is the leading cause of death. However, despite their high level of homology with humans, mice don't develop lung disease like people with cystic fibrosis do. Now, researchers have taken the first step towards developing a cystic fibrosis model that more accurately mirrors the disease in humans. And guess what they're ... Read More

Researchers say the results should now be tested in human clinical trials associated with muscle wasting, including Duchenne muscular dystrophy, which is the most prevalent form of the childhood disorder. In the study, mice of varying ages with disorders similar to Duchenne muscular dystrophy were injected with a safe virus that contained the protein follistatin. The protein inhibits the activity of myostatin, which previous studies demonstrated to lessen muscle growth. Both young and old mice that were treated with the therapy showed increases in muscle mass and boosts in strength. Because ... Read More

It had been suggested that diacetyl, one of the compounds that gives butter its distinctive yummy flavor (and a key ingredient in margarines and oils), could pose severe health risks when heated and inhaled for long periods of time. In fact, workers in several factories churning out artificial butter flavoring have come down with a rare and dire disease of the lungs called bronchiolitis obliterans. Most of the cases have been found in young, healthy, non-smoking men, and there are no known cures for the disease except a lung transplant. Now a new study confirms that prolonged exposure to ... Read More

The critters were Perdido Key beach mice, and the officials raced to evacuate them because only a few hundred remained in the wild. And those lived exclusively in sand-dune tunnels on a barrier island near Pensacola, Fla., in the path of the hurricane on the state's panhandle. Listed as an endangered species in 1985, Perdido Key beach mice, whose light-colored coat blends in with the region's white sand beaches, have suffered from previous storms; the species was nearly wiped out by hurricanes Erin and Opal in the mid-1990s. But working with the U.S. Fish and Wildlife Service, the Florida ... Read More