Fig. 4: Oxa-iboga analogs do not show pro-arrhythmia risk in adult human primary cardiomyocytes.
From: Oxa-Iboga alkaloids lack cardiac risk and disrupt opioid use in animal models
a Human heart is digested to isolate single cardiomyocytes, which are field stimulated to produce a regular pattern of contractility transients. These cells are phenotypically stable and provide a robust preclinical assay with high translational validity. b Representative traces capturing contraction-induced change in sarcomere length after administration of vehicle, noribogaine and oxa-noribogaine solutions. c Noribogaine demonstrates pro-arrhythmic potential by causing after-contractions and contraction failures in cardiomyocytes as quantified in the plot, providing validation of this assay for the iboga compounds. No pro-arrhythmic potential was detected for oxa- or epi-oxa-noribogaine (for donor information and replicates see Supplementary Fig. S8). Source data are provided in the Source Data file. Alternans % (percentage of repetitive alternating short and long contractility amplitude transients), STV % (Short-Term Variability in percentage).
