The Heart is a Smart Pump: Mechanotransduction Mechanisms of the Frank-Starling Law and the Anrep Effect.

The Frank-Starling law and Anrep effect describe two intrinsic mechanisms that regulate contraction force in the heart. Based on recent advancements and the historical literature, we propose new perspectives and address several critical issues in this review. () The Frank-Starling mechanism and Anrep effect are dynamically linked and act synergistically.

Beta-Adrenergic Activation of the Inward Rectifier K Current Is Mediated by the CaMKII Pathway in Canine Ventricular Cardiomyocytes.

Several ion currents in the mammalian ventricular myocardium are substantially regulated by the sympathetic nervous system via β-adrenergic receptor activation, including the slow delayed rectifier K current and the L-type calcium current. This study investigated the downstream mechanisms of β-adrenergic receptor stimulation by isoproterenol (ISO) on the inward rectifier (I) and the rapid delayed rectifier (I) K currents using action potential voltage clamp (APVC) and conventional voltage clamp techniques in isolated canine left ventricular cardiomyocytes. I and I were dissected by 50 µM BaCl and 1 µM E-4031, respectively.

Correction: Kovács et al. ABT-333 (Dasabuvir) Increases Action Potential Duration and Provokes Early Afterdepolarizations in Canine Left Ventricular Cells via Inhibition of I. 2023, , 488.

Text Correction [...

Relationship between ion currents and membrane capacitance in canine ventricular myocytes.

Current density, the membrane current value divided by membrane capacitance (C), is widely used in cellular electrophysiology. Comparing current densities obtained in different cell populations assume that C and ion current magnitudes are linearly related, however data is scarce about this in cardiomyocytes. Therefore, we statistically analyzed the distributions, and the relationship between parameters of canine cardiac ion currents and C, and tested if dividing original parameters with C had any effect.

INNOVATIVE TECHNIQUES AND NEW INSIGHTS: Studying cardiac ionic currents and action potentials in physiologically relevant conditions.

Cardiac arrhythmias are associated with various forms of heart diseases. Ventricular arrhythmias present a significant risk for sudden cardiac death. Atrial fibrillations predispose to blood clots leading to stroke and heart attack.