Key Points
- This research aims to compare the electrophysiological properties of myocytes from normal and hypertrophied feline left ventricles during metabolic inhibition.
- Induced chronic pressure overload in feline subjects under surgical anesthesia.
- Used a single-pipette, whole cell clamp method to record action potential and membrane currents from myocytes.
- Exposed myocytes to 1 mM CN- to assess response during metabolic inhibition.
- In hypertrophied cells, APD90 and APD0mV were longer before CN- exposure.
- ICa,L showed a significantly longer slow inactivation time constant in hypertrophied cells, while IK showed a smaller current density.
- During CN- exposure, APD shortened more in hypertrophied cells; amplitude of ICa,L decreased, affecting inactivation kinetics.
Structured PICO
PPopulationEndocardial myocytes enzymatically dissociated from normal and hypertrophied feline left ventricle (chronic pressure overload model)
IInterventionMetabolic inhibition by 1 mM CN-
CComparatorNormal feline left ventricular myocytes
OOutcomeAction potential duration (APD) and membrane currents (ICa,L and IK)surrogate
Hypertrophied feline left ventricular myocytes exhibit enhanced action potential shortening during metabolic inhibition, driven primarily by changes in L-type calcium currents.