Scyllatoxin.
A Potent Blocker of K\Ca\2 (SK) K+ Channels.
Scyllatoxin is a 31 amino acid long toxin, originally isolated from the Leiurus quinquestriatus hebraeus scorpion venom, and is classified as alpha-KTx 5.1 scorpion toxin family, having three disulfide bridges.
Scyllatoxin was shown to compete with \125\I -apamin binding in the brain. Furthermore, Scyllatoxin appears to be selective for apamin-sensitive SK channels.
Scyllatoxin inhibits apamin-sensitive SK channel activity in guinea-pig and rabbit hepatocytes, SK currents in human lymphoblastoma cells, and epinephrine-induced relaxation of visceral smooth muscle.
Scyllatoxin also inhibits the apamin-sensitive after hyperpolarization that follows action potentials in skeletal muscle and neurons.
The SK channel-mediated after hyperpolarising current (I\AHP\) of dorsal vagal neurons, presuming K\Ca\2.3 (SK3), were blocked by Scyllatoxin (20�30 nM). HEK 293 cell currents stably expressing hK\Ca\2.1 (hSK1) and K\Ca\2.2 (hSK2) were blocked by Scyllatoxin with an�IC50 of 80 nM and 287 pM, respectively.
Alomone Labs is pleased to offer Scyllatoxin (#STS-370), a highly potent blocker of K\Ca\ channels with highest affinity towards K\Ca\2.2, having the following affinities: K\Ca\2.2 < < K\Ca\2.3 < K\Ca\2.1.
Ion Channel Modulators; K+ Channel Blockers