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Differences in open state of NBA-modified cardiac Na+ channels


Patch clamp recordings from neonatal cardiac Na+ channels treated with N-bromoacetamide (NBA, 5–50 x 10-mol/l) showed modified Na+ channel activity. By chemical removal of inactivation, repetitive openings with an increased life time and burst-like activity occurred. NBA-modified Na+ channels differ in life time and may attain either a slightly (mean open time 3.1±0.2 ms) or a strongly (mean open time 15.2±1.4 ms) prolonged open state. This strongly suggests a heterogeneous population of NBA-modified Na+ channels in newborn rat cardiocytes.

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Kohlhardt, M., Fichtner, H. & Fröbe, U. Differences in open state of NBA-modified cardiac Na+ channels. Eur Biophys J 15, 289–292 (1988).

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Key words

  • Patch clamp
  • cardiac Na+ channels
  • channel modification
  • heterogeneous population