title: Alteration in surface muscle electrical anisotropy in the rat SOD1 model of amyotrophic lateral sclerosis.
abstract: OBJECTIVE
  To evaluate the effects of progressive neurogenic change on surface-measured anisotropy via study in the rat superoxide dismutase 1 (SOD1) G93A amyotrophic lateral sclerosis (ALS) model.
  
  
  METHODS
  Eight male ALS rats were studied over a period of 10 weeks. In each, the 20 kHz to 1 MHz electrical impedance of the gastrocnemius-soleus complex was measured with electrodes placed at 0° and at 90° relative to the major muscle fiber direction. The major outcome measure, the anisotropy difference (AD) for each of the resistance, reactance, and phase, was calculated as 90-0° values.
  
  
  RESULTS
  All three parameters showed substantial alterations with disease progression. However, the phase AD demonstrated the most substantial change, increasing from 1.8±1.58° to 10.2±2.13° (mean±standard error) comparing the first and last set of measurements (p=0.028).
  
  
  CONCLUSIONS
  Anisotropy increases substantially with disease progression in the ALS rat.
  
  
  CONCLUSIONS
  Measurement of surface electrical anisotropy offers a non-invasive means for quantifying neurogenic change in muscle.
authors: Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
authors: Jia
authors: J
authors: Li
authors: Seward B
authors: SB
authors: Rutkove
mesh_terms: D000690:Amyotrophic Lateral Sclerosis / Q000201:enzymology* / Q000503:physiopathology*; D000818:Animals; D016880:Anisotropy; D004195:Disease Models, Animal; D018450:Disease Progression; D017097:Electric Impedance; D008297:Male; D051381:Rats; D013482:Superoxide Dismutase / Q000235:genetics / Q000502:physiology*; D000072105:Superoxide Dismutase-1
chemical_list: C000606292:Sod1 protein, rat; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1