Noisy stimulation effect in calcium dynamics on cardiac cells

Area of Science:

• Cardiovascular Physiology
• Cellular Electrophysiology
• Biophysics

Background:

• Environmental and biological noise can influence physiological systems.
• Excitable cells, like cardiac cells, respond to external stimuli.
• Cardiac function relies on precise calcium dynamics within pacemaker and myocardial cells.

Purpose of the Study:

• To investigate the impact of Gaussian white noise on calcium dynamics in pacemaker and myocardial cells.
• To determine if noise can alter calcium handling in response to periodic electrical stimuli.
• To elucidate the role of noise in the function of key cardiac cell types.

Main Methods:

• Utilized imaging signals to quantify calcium dynamic parameters.
• Applied Gaussian white noise to periodic electrical stimuli delivered to cardiac cells.
• Compared responses between pacemaker and myocardial cells under noisy conditions.

Main Results:

• Low-intensity noise was found to enhance the amplitude and rate of calcium dynamics.
• Pacemaker cells demonstrated resilience, showing no significant effect from noisy stimuli.
• Myocardial cells exhibited altered calcium dynamics in response to noise.

Conclusions:

• Noise can modulate calcium dynamics in myocardial cells, potentially affecting cardiac contractility.
• Pacemaker cells appear less susceptible to the direct effects of noise on calcium signaling.
• These findings highlight a significant, previously underappreciated role for noise in cardiac electrophysiology and calcium handling.