Penitrem A (12627-35-9) is a fungal mycotoxin that acts as a selective, irreversible blocker of the smooth muscle high conductance Ca2+-activated K+ (BK, KCa1.1) channel (100% block at 10 nM).1 Displays brain neurotoxicity in rats along with dose-dependent convulsions and death.2 An important tool for studying the role of BK channels in vascular function which is effective in cellular, tissue and in vivo experiments.3 Inhibits BK channels in inside-out and cell-attached patches, whereas iberiotoxin (considered the gold standard BK channel blocker) does not.3 May be used to partially ablate Purkinje cells in immature rat cerebellum providing a model for neural stem cell transplantation studies.4
CAUTION: Penitrrem A is a potent toxin. Take proper precautions to prevent ingestion, inhalation and skin contact.
1) Knaus et al. (1994), Tremorgenic Indole Alkaloids Potently Inhibit Smooth Muscle High-Conductance Calcium-Activated Potassium Channels; Biochemistry, 33 5819
2) Breton et al. (1998), Brain neurotoxicity of Penitrem A: electrophysiological, behavioral and histopathological study: Toxicon., 36 645
3) Asano et al. (2012), Penitrem A as a tool for understanding the role of large conductance Ca(2+)/voltage-sensitive K(+) channels in vascular function; J. Pharmacol. Exp.Ther., 342 453
4) Lu et al. (2008), Toxin-produced Purkinje cell death: a model for neural stem cell transplantation studies; Brain Res. 1207 207