“…For voltage‐gated Na + channels, plant alkaloids, including ajmaline, act at six or more distinct receptor sites on the channel protein ( Wink, 1993 , 2000 ; Cestele and Catterall, 2000 ). Further evidence comes from blocking effects of ajmaline on L‐type Ca 2+ currents in ventricular myocytes ( Bebarova et al ., 2005b ) and dual effects of prajmaline on Ca 2+ currents in frog cardiomyocytes ( Alvarez and Vassort, 1991 ). This is expected from the high homology of the voltage‐dependent Na + , K + and Ca 2+ channels ( Catterall, 1988 ; Lehmann‐Horn and Jurkat‐Rott, 1999 ).…”