Charybdotoxin blocks both Ca‐activated K channels and Ca‐independent voltage‐gated K channels in rat brain synaptosomes
- 3 July 1989
- journal article
- Published by Wiley in FEBS Letters
- Vol. 250 (2) , 433-436
- https://doi.org/10.1016/0014-5793(89)80771-9
Abstract
Charybdotoxin (ChTX), a 4.3 kDa polypeptide toxin from the venom of the scorpion Leiurus quinquestriatus , blocks both a Ca-activated K channel (IC 50 ≈ 15 nM) and a Ca-independent voltage-gated K channel (IC 50 ≈ 40 nM) in rat brain synaptosomes. These results indicate that in this preparation ChTX is not specific for the Ca-activated K channel and suggest that there may be structural homology among the toxin-binding sites on various types of K channels.Keywords
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