Group I nonreciprocal inhibition in primary restless legs syndrome.
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.
Scaglione
Cesa
C
Department of Neurological Sciences, University of Bologna, Bologna, Italy. cesa.scaglione@unibo.it
Vetrugno
Roberto
R
Plazzi
Giuseppe
G
Rizzo
Giovanni
G
Provini
Federica
F
Montagna
Pasquale
P
Martinelli
Paolo
P
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