The activation effect of hainantoxin-I, a peptide toxin from the Chinese spider, Ornithoctonus hainana, on intermediate-conductance Ca2+-activated K+ channels.

ABSTRACT: Intermediate-conductance Ca2+-activated K+ (IK) channels are calcium/calmodulin-regulated voltage-independent K+ channels. Activation of IK currents is important in vessel and respiratory tissues, rendering the channels potential drug targets. A variety of small organic molecules have been synthesized and found to be potent activators of IK channels. However, the poor selectivity of these molecules limits their therapeutic value. Venom-derived peptides usually block their targets with high specificity. Therefore, we searched for novel peptide activators of IK channels by testing a series of toxins from spiders. Using electrophysiological experiments, we identified hainantoxin-I (HNTX-I) as an IK-channel activator. HNTX-I has little effect on voltage-gated Na+ and Ca2+ channels from rat dor

SUBMITTER: Huang P 

PROVIDER: S-EPMC4147597 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature