Iberiotoxin (TFA)

Iberiotoxin (TFA) is a selective high conductance high conductance Ca2+-activated K+ channel inhibitor with a Kd of ~1 nM. Iberiotoxin (TFA) does not block other types of voltage-dependent ion channels[1][2][3].

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[1]Galvez A, et al. Purification and characterization of a unique, potent, peptidyl probe for the high conductance calcium-activated potassium channel from venom of the scorpion Buthus tamulus. J Biol Chem. 1990;265(19):11083-11090.|[2]Echeverry S, et al. Activation of BK Channel Contributes to PL-Induced Mesenchymal Stem Cell Migration. Front Physiol. 2020;11:210.|[3]Wang RJ, et al. Downregulation of large conductance calcium-activated potassium channels in paraventricular nucleus contributes to sympathoexcitation in rats with chronic heart failure. Zhonghua Xin Xue Guan Bing Za Zhi. 2018;46(3):178-186.