Key Points
- The aim is to estimate the permeability of the cardiac cell membrane to choline ions in cat ventricular muscle.
- Estimated choline permeability by measuring radioactive choline influx and efflux in cat ventricular muscle.
- Analyzed the intracellular choline concentration after 2 hours of incubation with varying choline concentrations.
- Conducted paper chromatography of muscle extracts to assess choline metabolism.
- Maximum choline influx at 3.5 mM was 0.56 pmoles/cm².sec and at 137 mM was 9 pmoles/cm².sec.
- Choline efflux rates were estimated at 16-45 pmoles/cm².sec in 137 mM and at 1.3-3.5 pmoles/cm².sec in 3.5 mM choline.
- The data suggest that choline does not have an efficient active pumping mechanism due to intracellular accumulation.
Structured PICO
PPopulationCat ventricular muscle cells
IInterventionIncubation in 3.5 mM and 137 mM radioactive choline
OOutcomeCholine influx and efflux (permeability of the cardiac cell membrane to choline ions)surrogate
The study demonstrates significant choline permeability and accumulation in cat ventricular muscle cells, ruling out an efficient active pumping mechanism.