A highly selective K⁺- ionophore. It binds potassium ions (K⁺) and facilitates their transfer across lipid bilayers. Inhibits Ca²⁺-ATPase activity and promotes cell death by mitochondrial swelling and autophagic processes, but not apoptosis. Antagonizes endothelin-induced vasoconstriction (IC₅₀ = 0.3 µM).