Actions of flecainide on RyR2 channels in lipid bilayers, including RyR2 source, experimental conditions for the major experiments in each study, voltage examined and direction of current flow, and main results
| . | RyR2 source . | Solution ion concentrations (mM) . | Voltage . | Main effect of flecainide . |
|---|---|---|---|---|
| Watanabe et al. (2009) | Sheep heart | Current carrier—Cs+cis/trans 250/250 Cs+cis/trans 2/0 ATP cis/trans 0.1 × 10−3/1.0 Ca2+ or cis/trans 0.1/1.0 Ca2+ | +40 mV (current flow cis to trans) | Inhibition: IC50 = 15 µM: 0.1 × 10−3/1.0 mM Ca2+ IC50 = 55 µM: 0.1/1.0 mM Ca2+ |
| Hilliard et al. (2010) | Sheep heart | Current carrier—Cs+cis/trans 250/250 Cs+cis/trans 2/0 ATP cis/trans 0.1 × 10−3/1.0 Ca2+ | +40 mV | Open state block (+40 mV) IC50 = 16 µM |
| Hwang et al. (2011) | CSQ2−/− mouse heart | Current carrier—Cs+cis/trans 250/250 Cs+cis/trans 2.0/0 ATP cis/trans 0.1 × 10−3/1.0 Ca2+ | +40 mV | IC50 for Open state block at +40 mV: Flecainide ∼16 µM R-propafenone ∼12 µM S-propafenone ∼25 µM |
| Mehra et al. (2014) | Sheep heart | Current carrier—Cs+trans 250 Cs+cis/trans 2.0/0 ATP trans 0.1 Ca2+ cis Cs+, Ca2+, Mg2+ concentration and pH and caffeine addition varied | +40 and −40 mV (current flow trans to cis) | Modes of block at +40 mV: (1) fast—reduced open times (2) slow—prolonged closures (3) substate with fast block (4) burst length depends on cis [Ca2+] IC50 at −40 mV >100-fold greater than that at +40 mV |
| Bannister et al. (2015) | Recombinant human RyR2 | Current carrier—K+cis/trans 610/610 KCl cis EMD 41000 | +40 and −40 mV | 1–50 µM blocks to a substate level at +40 mV No effect of 50 µM flecainide at −40 mV trans to cis flux No effect on trans to cis K+ flux at 0 mV with 250/50 mM [K+] No effect on trans to cis Ca2+ flux at 0 mV—flux driven by a 100-fold trans to cis [Ca2+] gradient |
| Bannister et al., (2016) | Recombinant human RyR2 | Current carrier—K+cis/trans 610/610 KCl cis EMD 41000 | +40 mV and −40 mV | Flecainide analogues QX-FL and NU-FL are less potent blockers of cis to trans current Trans to cis current not altered by flecainide or its analogues |
| Kryshtal et al. (2021) | Sheep heart | Current carrier—Cs+cis/trans 250/250 Cs+cis/trans 2.0/0 ATP cis/trans 0.1 × 10−3/1.0 Ca2+ max phosphorylation of RyR2 S2808 and S2814 | +40 mV | QX-FL and NU-FL are less effective at blocking RyR2 channels but equally effective in blocking Na+ channels, with parallel effects on SR Ca2+ release (Table 2) |
| Salvage et al. (2021a) | WT and P2328S+/+ mouse RyR2 | Current carrier—Cs+cis/trans 250/250 Cs+cis/trans 1 × 10−3/1.0 Ca2+ | +40 mV and −40 mV | WT and mutant channels show voltage-independent (1) inhibition with ≥5 µM, and (2) activation of lower activity channels with ≥0.5 µM |
| . | RyR2 source . | Solution ion concentrations (mM) . | Voltage . | Main effect of flecainide . |
|---|---|---|---|---|
| Watanabe et al. (2009) | Sheep heart | Current carrier—Cs+cis/trans 250/250 Cs+cis/trans 2/0 ATP cis/trans 0.1 × 10−3/1.0 Ca2+ or cis/trans 0.1/1.0 Ca2+ | +40 mV (current flow cis to trans) | Inhibition: IC50 = 15 µM: 0.1 × 10−3/1.0 mM Ca2+ IC50 = 55 µM: 0.1/1.0 mM Ca2+ |
| Hilliard et al. (2010) | Sheep heart | Current carrier—Cs+cis/trans 250/250 Cs+cis/trans 2/0 ATP cis/trans 0.1 × 10−3/1.0 Ca2+ | +40 mV | Open state block (+40 mV) IC50 = 16 µM |
| Hwang et al. (2011) | CSQ2−/− mouse heart | Current carrier—Cs+cis/trans 250/250 Cs+cis/trans 2.0/0 ATP cis/trans 0.1 × 10−3/1.0 Ca2+ | +40 mV | IC50 for Open state block at +40 mV: Flecainide ∼16 µM R-propafenone ∼12 µM S-propafenone ∼25 µM |
| Mehra et al. (2014) | Sheep heart | Current carrier—Cs+trans 250 Cs+cis/trans 2.0/0 ATP trans 0.1 Ca2+ cis Cs+, Ca2+, Mg2+ concentration and pH and caffeine addition varied | +40 and −40 mV (current flow trans to cis) | Modes of block at +40 mV: (1) fast—reduced open times (2) slow—prolonged closures (3) substate with fast block (4) burst length depends on cis [Ca2+] IC50 at −40 mV >100-fold greater than that at +40 mV |
| Bannister et al. (2015) | Recombinant human RyR2 | Current carrier—K+cis/trans 610/610 KCl cis EMD 41000 | +40 and −40 mV | 1–50 µM blocks to a substate level at +40 mV No effect of 50 µM flecainide at −40 mV trans to cis flux No effect on trans to cis K+ flux at 0 mV with 250/50 mM [K+] No effect on trans to cis Ca2+ flux at 0 mV—flux driven by a 100-fold trans to cis [Ca2+] gradient |
| Bannister et al., (2016) | Recombinant human RyR2 | Current carrier—K+cis/trans 610/610 KCl cis EMD 41000 | +40 mV and −40 mV | Flecainide analogues QX-FL and NU-FL are less potent blockers of cis to trans current Trans to cis current not altered by flecainide or its analogues |
| Kryshtal et al. (2021) | Sheep heart | Current carrier—Cs+cis/trans 250/250 Cs+cis/trans 2.0/0 ATP cis/trans 0.1 × 10−3/1.0 Ca2+ max phosphorylation of RyR2 S2808 and S2814 | +40 mV | QX-FL and NU-FL are less effective at blocking RyR2 channels but equally effective in blocking Na+ channels, with parallel effects on SR Ca2+ release (Table 2) |
| Salvage et al. (2021a) | WT and P2328S+/+ mouse RyR2 | Current carrier—Cs+cis/trans 250/250 Cs+cis/trans 1 × 10−3/1.0 Ca2+ | +40 mV and −40 mV | WT and mutant channels show voltage-independent (1) inhibition with ≥5 µM, and (2) activation of lower activity channels with ≥0.5 µM |
Publications are listed in chronological order.