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Updated: Aug 22, 2026

Voltage-Dependent Potassium Current Recording on H9c2 Cardiomyocytes via the Whole-Cell Patch-Clamp Technique
Published on: November 11, 2022
Tetrahydroacridine inhibits voltage-dependent Na(+) current in guinea-pig ventricular myocytes
Wei Wang1, Yi-Ping Wang, Guo-Yuan Hu
1State Key Laboratory of Drug Research, The First Department of Pharmacology, Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 201203, China.
Aim:
To study the effects of tetrahydroacridine (tacrine) on voltage-gated Na(+) channels in cardiac tissues.
Methods:
Single ventricular myocytes were enzymatically dissociated from adult guinea-pig heart. Voltage-dependent Na(+) current was recorded using whole cell voltage-clamp technique.
Results:
(1) Tacrine reversibly inhibited Na(+) current with an IC(50) value of 120 micromol/L (95 % confidence range: 108-133 micromol/L). (2) The inhibitory effects of tacrine on Na(+) current exhibited both a tonic nature and use-dependence. (3) Tacrine at 100 micromol/L caused a negative shift (about 10 mV) in the voltage-dependence of steady-state inactivation of Na(+) current, and retarded its recovery from inactivation, but did not affect its activation curve. (4) Intracellular application of tacrine significantly inhibited Na(+) current.
Conclusion:
In addition to blocking other voltage-gated ion channels, tacrine blocked Na(+) channels in guinea-pig ventricular myocytes. Tacrine acted as inactivation stabilizer of Na(+) channels in cardiac tissues.
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