Eur J Pharmacol 1998 Jan 19;3421:93-104. doi: 10.1016/s0014-2999(97)01420-9.

Effects of bisaramil, a novel class I antiarrhythmic agent, on heart, skeletal muscle and brain Na+ channels.

Abstract
The effects of bisaramil, a novel diazabicyclononane antiarrhythmic agent, were compared to those of lidocaine, a clinically used class Ib antiarrhythmic agent, on heart, skeletal muscle and brain Na+ channels expressed in Xenopus laevis oocytes using a two-electrode voltage clamp. Both bisaramil and lidocaine produced a concentration-dependent tonic block of Na+ current that was most effective on cardiac channels, but bisaramil was more potent than lidocaine. Both drugs produced a concentration-dependent shift in the voltage-dependence of inactivation and delayed recovery from inactivation. Bisaramil produced marked frequency-dependent block of heart channels and mild frequency-dependent block of skeletal muscle and brain channels, whereas lidocaine produced marked frequency-dependent block of all three channel types. Therefore, bisaramil shows tonic and frequency-dependent blockade that is most potent against the heart Na+ channel, which may account for its potent antiarrhythmic efficacy in vivo, and may result in reduced central nervous system toxicity compared to clinically used agents such as lidocaine.

PubMed ID: 9544797
Article link: Eur J Pharmacol
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