Klinische Neurophysiologie 2010; 41 - ID106
DOI: 10.1055/s-0030-1250935

Impaired motor cortex plasticity in patients with Noonan-Syndrome

F Mainberger 1, M Zenker 2, N Jung 1, I Delvendahl 1, A Brandt 1, L Freudenberg 1, V Mall 1
  • 1Uniklinik Freiburg, Neuropädiatrie, Freiburg, Deutschland
  • 2Universität, Humangenetik, Magdeburg, Deutschland

Introduction: Noonan Syndrome (NS) is caused by a mutation of genes, leading to hyperactivation of the Ras-pathway. Recent in vitro studies demonstrated a Long Term Potentiation (LTP) impairment caused by RAS-pathway hyperactivity.

Methods: In this study 8 patients with Noonan-Syndrome (mean 26.25±11.25 years, 5 female, 3 male) and an age and gender matched control group (mean 25.13±3.44 years, 5 female, 3 male) were investigated using paired associated stimulation (PAS). Changes in MEP amplitude were investigated before, immediately after (post 1), 30 (post2) and 60 (post 3) minutes after PAS.

Results: We demonstrated that MEP amplitudes of healthy controls did increase significantly from 1.03±0.18 to 1.81±0.61 mV (Post 3: p=0.006, paired t test), which was not seen in patients with Noonan-Syndrome 0.88±0.1 to 1.2±0.49 mV and that there was a significant difference between both groups at this point in time (p=0.044, unpaired t test).

Discussion: In conclusion, synaptic plasticity in patients with NS is impaired which may be caused by constitutive activity of the Ras pathway.