Dopamine and the spinal cord in restless legs syndrome: does spinal cord physiology reveal a basis for augmentation?
The pathophysiology of restless legs syndrome (RLS) is incompletely understood. L-DOPA, as the precursor of dopamine, as well as dopamine agonists, plays an essential role in the treatment of RLS leading to the assumption of a key role of dopamine function in the pathophysiology of RLS. Periodic limb movements in sleep are a key feature of RLS. They are generated in the spinal cord. Here we review RLS phenomenology on the basis of known dopaminergic influence on spinal control, which has been studied a great deal in recent decades in animals. In particular, we propose that the differential effects of l-DOPA and opioids on early and late flexor reflexes may be linked to the phenomenon of augmentation.
Paulus
Walter
W
Department of Clinical Neurophysiology, University of Göttingen, Robert Koch Str. 40, 37075 Göttingen, Germany. wpaulus@med.uni-goettingen.de
Schomburg
Eike D
ED
D000344:Afferent Pathways / Q000378:metabolism / Q000503:physiopathology; D004298:Dopamine / Q000378:metabolism*; D018491:Dopamine Agonists / Q000627:therapeutic use*; D004525:Efferent Pathways / Q000378:metabolism / Q000503:physiopathology; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use*; D009294:Narcotics / Q000627:therapeutic use; D012148:Restless Legs Syndrome / Q000188:drug therapy / Q000378:metabolism* / Q000503:physiopathology*; D013116:Spinal Cord / Q000378:metabolism* / Q000503:physiopathology*
D018491:Dopamine Agonists; D009294:Narcotics; D007980:Levodopa; D004298:Dopamine