Running boosts nerve talk in injured rats.
Exercise speeds the recovery of rats with spinal cord injuries, a new study suggests. Regular runs prompt the release of chemicals that help damaged nerve cells communicate. The finding adds to evidence that workouts may hasten Rehabilitation in humans with spinal cord injuries.
Every year in the United States alone, around 15,000 people damage their spine. Physical Therapy improves muscle strength and reduces pain, but most are left with some degree of permanent paralysis.
Like some humans, a proportion of rats with partially severed spinal cords can learn to walk again. Given a wheel to run in, their recovery time halves to just one month, Fernando Gómez-Pinilla from the University of California, Los Angeles told this week’s Society for Neuroscience Annual Meeting in New Orleans. Rats take to the exercise naturally and run up to 4 kilometres a night.
Patients should be helped to exercise on their feet, agrees spinal cord researcher Oswald Steward from the University of California at Irvine. Evidence like this helps rehabilitation experts hone their methods, he explains: “For years, we’ve been teaching patients with spinal cord injuries to sit”.
Injured rats that run have three times more BDNF – a molecule that promotes cell survival – than inactive rodents, reports Gómez-Pinilla. They also have higher levels of synapsin 1, a protein that helps neurons release chemical messengers.
Drugs that mimic these effects could aid healing in some paralyzed patients, speculates neurophysiologist Lorne Mendell from the State University of New York, Stony Brook. “We’re beginning to understand the molecular mechanisms that relate exercise to spinal cord repair,” he says.
© Nature News Service / Macmillan Magazines Ltd 2003