Restless Legs Syndrome (RLS) is a chronic neurological sensorimotor disorder characterized by an irritable urge to move the affected body part (usually the legs). These sensations range from "creepy-crawling" feelings to pain-like symptoms that severely disrupt sleep and that usually require life-long treatment.
The classical and initially highly effective RLS treatment with dopamine agonists usually fails over time, leading to a worsening of the symptoms with the treatment (augmentation). There are currently no available treatments that specifically target this dopamine-associated augmentation in RLS.
Stefan Clemens, PhD, of the Department of Physiology at the Brody School of Medicine at East Carolina University, discovered in an animal model that treatment of RLS with a dopamine 3 receptor agonist switches pain reflexes from analgesic effects (early) to hyperalgesic states (with long-term treatment), mimicking the switch in sensory effects observed in patients with augmentation.
His lab found in the animal model that, by blocking dopamine 1 receptor activation in animals previously treated with dopamine 3 receptor agonist, animal behavior returned from hyperalgesic to normal behavioral ranges. If these findings can be translated to RLS patients, this will allow for the patient's pain sensitivity to return to normal.
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