Voltage-activated sodium currents in a cell line expressing a Cu,Zn superoxide dismutase typical of familial ALS.
The whole-cell configuration of the patch-clamp recording was used to study the voltage-dependent Na+ currents in a model system for the familial form of amyotrophic lateral sclerosis (ALS) associated with mutations in Cu,Zn superoxide dismutase. Here we report that the amplitude of voltage-gated Na+ currents is significantly reduced in cell lines expressing mutant Cu,Zn superoxide dismutase G93A when compared with the parental, untransfected cell line and to a cell line expressing the wild-type enzyme. This effect is associated with a shift toward positive values of the steady-state inactivation curve of the Na+ currents. These results indicate that expression of a Cu,Zn superoxide dismutase typical of patients affect with familial ALS influence the functionality of the voltage-dependent Na+ channels; this effect may contribute to the pathogenesis of the disease.
Zona
C
C
Dipartimento di Neuroscienze, Università di Roma Tor Vergata, Rome, Italy.
Ferri
A
A
Gabbianelli
R
R
Mercuri
N B
NB
Bernardi
G
G
Rotilio
G
G
Carri
M T
MT
D015761:4-Aminopyridine / Q000494:pharmacology; D000690:Amyotrophic Lateral Sclerosis / Q000378:metabolism*; D002104:Cadmium / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D004558:Electric Stimulation; D006801:Humans; D015640:Ion Channel Gating / Q000502:physiology; D009154:Mutation / Q000502:physiology; D009410:Nerve Degeneration / Q000378:metabolism; D009447:Neuroblastoma; D009474:Neurons / Q000737:chemistry / Q000201:enzymology; D018384:Oxidative Stress / Q000502:physiology; D018408:Patch-Clamp Techniques; D011188:Potassium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism*; D015222:Sodium Channels / Q000502:physiology*; D013482:Superoxide Dismutase / Q000235:genetics* / Q000378:metabolism; D014407:Tumor Cells, Cultured
D015222:Sodium Channels; D002104:Cadmium; D012964:Sodium; D015761:4-Aminopyridine; D013482:Superoxide Dismutase; D011188:Potassium; D002118:Calcium