title: Group I nonreciprocal inhibition in primary restless legs syndrome.
abstract: Electrophysiological investigations of restless legs syndrome (RLS) have found spinal circuits impinging on motoneurones. We evaluated the H reflex threshold, latency, the Hmax/Mmax ratio, and the short latency autogenic inhibition in 7 patients with RLS and 10 age-matched controls by testing the excitability changes in soleus H reflex Ib interneuron function. A significant reduction in Ib inhibition at 4 (P = 0.043), 5 (P = 0.007), and 6 ms (P = 0.001) of H reflex conditioning interstimulus interval was found in RLS patients. Data support the hypothesis that altered group I nonreciprocal inhibition is implicated in enhancing the spinal circuitry excitability of RLS, and are consistent with the view of an abnormal supraspinal drive to spinal interneurons in RLS.
authors.affiliation: Department of Neurological Sciences, University of Bologna, Bologna, Italy. cesa.scaglione@unibo.it
authors.forename: Cesa
authors.initials: C
authors.lastname: Scaglione
authors.forename: Roberto
authors.initials: R
authors.lastname: Vetrugno
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Plazzi
authors.forename: Giovanni
authors.initials: G
authors.lastname: Rizzo
authors.forename: Federica
authors.initials: F
authors.lastname: Provini
authors.forename: Pasquale
authors.initials: P
authors.lastname: Montagna
authors.forename: Paolo
authors.initials: P
authors.lastname: Martinelli
mesh_terms: D004594:Electrophysiology; D006181:H-Reflex / Q000502:physiology; D006801:Humans; D020646:Intralaminar Thalamic Nuclei / Q000503:physiopathology; D009046:Motor Neurons / Q000502:physiology*; D009415:Nerve Net / Q000503:physiopathology*; D009433:Neural Inhibition / Q000502:physiology*; D012148:Restless Legs Syndrome / Q000175:diagnosis* / Q000503:physiopathology*; D012154:Reticular Formation / Q000503:physiopathology; D013127:Spinal Nerves / Q000503:physiopathology*; D011795:Surveys and Questionnaires