Margatoxin is a non-selective inhibitor of human Kv1.3 K+ channels

Human T cells in silico: Modelling their electrophysiological behaviour in health and disease

“…A recent publication reports on non-specific side effects through its additional binding of K V 1.1 and K V 1.2 channels (Bartok et al, 2014). Due to the ubiquitous expression of these K + channels the authors of that study consider the in vivo usage of MgTx as being critical.…”

Role of automated patch-clamp systems in drug research and development

“…anuroctoxin APA action potential amplitude APD 50 action potential duration measured at 50% of repolarization APD 90 action potential duration measured at 90% of repolarization C. majus Chelidonium majus…”

“…Chinese hamster ovary K1 cell line DEA desethylamiodarone DMEM Dulbecco's modified Eagle's medium DMSO dimethyl sulfoxide EC 50 half maximal effective concentration EDTA ethylenediaminetetraacetic acid EGTA ethylene glycol tetraacetic acid FBS fetal bovine serum GABA gamma-aminobutyric acid GIRK G protein-coupled inwardly rectifying potassium channel GTPγS guanosine-5'-(γ-thio)-triphosphate HEK293 human embryonic kidney 293 cell line HEPES 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid HCN hyperpolarization-activated cyclic nucleotide-gated channel hERG human ether-a-go-go-related gene I Ca,L L-type Ca 2+ current I f funny or pacemaker current I KACh acetylcholine receptor operated potassium current I Kr rapid delayed rectifier potassium current I Ks slow component of the delayed rectifier potassium current I to transient outward potassium current IC 50 half maximal inhibitory concentration IMDM Iscove's modified Dulbecco's medium MEM minimum essential medium MgTx margatoxin PBS phosphate buffered saline TEA tetraethylammonium RP resting potential RPMI 1640 Roswell Park Memorial Institute 1640 medium RP-silica gel reversed-phase silica gel RP-HPLC reversed-phase high-performance liquid chromatography RT room temperature V max maximum upstroke velocity Defined by the stimulus necessary to evoke activity, the majority of ion channels are commonly classified into two main subgroups: voltage-gated and ligand-gated channels. The most important difference is that voltage-gated ion channels are activated by changes in plasma membrane potential, while ligand-gated channels activated by endogenous ligands [3][4][5] [10].…”

“…Both extracts revealed significant hERG ion channel inhibitory activity at room temperature with estimated IC 50 values of 8.31 ± 0.79 μg/ml and 5.09 ± 0.49 μg/ml (Figure 18). The hERG blocking potencies of the major alkaloids of the plant (sanguinarine, chelidonine, berberine and coptisine) were also evaluated and found that all alkaloids showed considerable inhibitory effect apart from coptisine ( Figure 19).…”

“…Unfortunately, the isolated compounds have only moderate activities on GIRK channel; therefore further studies are needed in order to identify minor compounds responsible for the potassium ion channel modulatory activity. Nevertheless, sotalol is among the least hydrophobic compounds [109], and numerous studies also reported extremely high IC 50 Increasing evidence indicates that the composition of native I Kr channels is very complex, and the α-subunit composition of the channel can affects its blocking sensitivity. The hERG1 gene encodes at least two transcripts: hERG1a, the original isolate, and hERG 1b, an alternate transcript [121] [122].…”