BUY Phrixotoxin-1

Phrixotoxin-1. K_v4.2 and K_v4.3 Potent Blocker.
Phrixotoxin 1 (PaTx1) is a 29 amino acid peptidyl toxin isolated from the venom of the theraphosid Phrixotrichus auratus, which potently blocks A-type K⁺ currents.
PaTx1 specifically blocks K_v4.3 and K_v4.2 currents with a 5 nM < IC₅₀ < 70 nM, by modifying the gating properties of these channels.

As with other spider toxins, PaTx1 presents an active molecular surface, including a hydrophobic patch surrounded by charged residues, which are important for their binding on K_v channels. Electrophysiological studies show that the PaTx1 blocks K_v4 channels via a mechanism similar to that of hanatoxins on K_v2 channels, as they bind and stabilize the preferentially closed state of the channel, in a voltage-dependent manner.

PaTx1 is a crucial tool for understanding the contribution of K_v4.3 and K_v4.2 in cardiac electrogenesis. Treatment of mice with PaTx1 results in numerous transient cardiac adverse reactions including the occurrence of premature ventricular beats, ventricular tachycardia, different degrees of atrioventricular (AV) blockage and prolongation of the QT interval.

Alomone Labs is pleased to offer Phrixotoxin-1, a natural peptide purified to homogeneity from the venom of the tarantula phrixotrichus auratus
Ion Channel Modulators; K⁺ Channel Blockers.