Open AccessArrhythmogenic effect of androgens on the rat heart
Author(s) -
Mariana Argenziano,
Gisela Tiscornia,
Rosalía Moretta,
Leonardo Casal,
María Constanza Potilinski,
Carlos Amorena,
Eduardo Garcia-Gras
Publication year - 2016
Publication title -
journal of physiological sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.968
H-Index - 49
eISSN - 1880-6562
pISSN - 1880-6546
DOI - 10.1007/s12576-016-0459-y
Subject(s) - repolarization , medicine , endocrinology , afterdepolarization , testosterone (patch) , electrophysiology , hormone , potassium channel , cardiac electrophysiology , cardiac action potential , membrane potential , ion channel , chemistry , biology , biophysics , receptor
In most species androgens shorten the cardiac action potential and reduce the risk of afterdepolarizations. Despite the central role of the rat model in physiological studies, the effects of androgens on the rat heart are still inconclusive. We therefore performed electrophysiological studies on the perfused rat right ventricular free wall. We found a correlation between androgenic activity and a propensity to generate ventricular ectopic action potentials. We also found that the testosterone treatment increased action potential duration at 90 % of repolarization (APD90), while androgenic inhibition increased the time to peak and decreased APD90. We observed that the voltage-gated potassium channel Kv4.3 and the bi-directional membrane ion transporter NCX in the rat myocardium were regulated by androgenic hormones. One possible explanation for these findings is that due to the expression of specific ion channels in the rat myocardium, the action potential response to its hormonal background is different from those described in other experimental models. Our results indicate that androgenic control of NCX expression plays a key role in determining arrhythmogenicity in the rat heart.