Triggered Ca²⁺ Waves Induce Depolarization of Maximum Diastolic Potential and Action Potential Prolongation in Dog Atrial Myocytes.

ABSTRACT:

Background

We have identified a novel form of abnormal Ca²⁺ wave activity in normal and failing dog atrial myocytes which occurs during the action potential (AP) and is absent during diastole. The goal of this study was to determine if triggered Ca²⁺ waves affect cellular electrophysiological properties.

Methods

Simultaneous recordings of intracellular Ca²⁺ and APs allowed measurements of maximum diastolic potential and AP duration during triggered calcium waves (TCWs) in isolated dog atrial myocytes. Computer simulations then explored electrophysiological behavior arising from TCWs at the tissue scale.

Results

At 3.3 to 5 Hz, TCWs occurred during the AP and often outlasted several AP cycles. Maximum diastolic potential was reduced, an

SUBMITTER: Gussak G 

PROVIDER: S-EPMC7340345 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature