The Bis(1,2,3,4-tetrahydroisoquinoline) Alkaloids Cepharanthine and Berbamine Are Ligands of SK Channels.

Cepharanthine, a multitarget alkaloid which has recently been shown to be effective against SARS-Cov-2, and berbamine, an alkaloid characterized as a calcium channel blocker, both share key structural elements with known small conductance calcium-activated potassium (SK) channel blockers. These structural similarities led us to evaluate their affinity for SK channels. Therefore, we performed binding on SK2 and SK3 subtypes and highlighted micromolar to sub-micromolar affinities.