Population
Ventricular cells isolated from rat heart
Comparison
Increase in stimulation rate from 0.3 to 3 Hz… vs Baseline stimulation rate of 0.3 Hz
Design
Preclinical
Key result
Increasing the stimulation rate from 0.3 to 3 Hz in isolated rat ventricular cells caused a gradual reduction in contraction amplitude and attenuation of the late phase of the action potential.
Authors
Loading...
No immediate clinical implications from rat cells; leaves open translation of rate-dependent calcium effects to human arrhythmias.
Increasing stimulation rate in rat ventricular cells alters action potential duration, inward currents, and contraction amplitude, effects that are dependent on depolarization duration and intracellular calcium handling.
Mitchell et al. (1985) studied this question. Increase in stimulation rate vs. 0.3 Hz was evaluated on Amplitude of contraction and late phase of the action potential. Increasing the stimulation rate from 0.3 to 3 Hz in isolated rat ventricular cells caused a gradual reduction in contraction amplitude and attenuation of the late phase of the action potential.