Penitrem A. Tremortin A. A Mycotoxin Blocker of KCa1.1 (BK) Channels.
Penitrem A is widely used to probe KCa1.1 channels in smooth muscle preparations, where it induces prolongation of the depolarization plateau potential. Penitrem A is a selective blocker of KCa1.1 (high-conductance Ca2+-activated K+, BK) channels. It belongs to a set of tremorgenic indole alkaloids which are lipid soluble and also include Verruculogen (#V-500) and Paxilline (#P-450). Penitrem A (400 mg mycelium/kg) increased the spontaneous release of endogenous glutamate, GABA (gamma-aminobutyric acid), and aspartate by 213%, 455%, and 277%, respectively, from rat cerebrocortical synaptosomes.Ion Channel Modulators; K+ Channel Blockers.