Cation selectivity and inhibition of malignant glioma Na+ channels by Psalmotoxin 1.

  title={Cation selectivity and inhibition of malignant glioma Na+ channels by Psalmotoxin 1.},
  author={James K. Bubien and Hong-Long Ji and G. Yancey Gillespie and Catherine M. Fuller and James M. Markert and Timothy B. Mapstone and Dale J. Benos},
  journal={American journal of physiology. Cell physiology},
  volume={287 5},
Psalmotoxin 1 (a component of the venom of a West Indies tarantula) is a 40-amino acid peptide that inhibits cation currents mediated by acid-sensing ion channels (ASIC). In this study we performed electrophysiological experiments to test the hypothesis that Psalmotoxin 1 (PcTX1) inhibits Na+ currents in high-grade human astrocytoma cells (glioblastoma multiforme, or GBM). In whole cell patch-clamped cultured GBM cells, the peptide toxin quickly and reversibly inhibited both inward and outward… 

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