Charybdotoxin blocks both Ca-activated K channels and Ca-independent voltage-gated K channels in rat brain synaptosomes
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چکیده
منابع مشابه
Charybdotoxin selectively blocks small Ca-activated K channels in Aplysia neurons
The action of charybdotoxin (ChTX), a peptide component isolated from the venom of the scorpion Leiurus quinquestriatus, was investigated on membrane currents of identified neurons from the marine mollusk, Aplysia californica. Macroscopic current recordings showed that the external application of ChTX blocks the Ca-activated K current in a dose- and voltage-dependent manner. The apparent dissoc...
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We have used a structure-based design strategy to transform the polypeptide toxin charybdotoxin, which blocks several voltage-gated and Ca(2+)-activated K(+) channels, into a selective inhibitor. As a model system, we chose two channels in T-lymphocytes, the voltage-gated channel Kv1.3 and the Ca(2+)-activated channel IKCa1. Homology models of both channels were generated based on the crystal s...
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A variety of scorpion venoms and purified toxins were tested for effects on ion channels in human T lymphocytes, a human T leukemia cell line (Jurkat), and murine thymocytes, using the whole-cell patch-clamp method. Nanomolar concentrations of charbdotoxin (CTX), a purified peptide component of Leiurus quinquestriatus venom known to block Ca2+-activated K+ channels from muscle, blocked "type n"...
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ژورنال
عنوان ژورنال: FEBS Letters
سال: 1989
ISSN: 0014-5793
DOI: 10.1016/0014-5793(89)80771-9