A single injection of periostin decreases cardiac voltage-gated Na + channel in rat ventricles

[摘要] Changes in electrophysiological properties, such as ion channel expression and activity, are closely related to arrhythmogenesis during heart failure (HF). However, a causative factor for the electrical remodeling in HF has not been determined. Periostin (POSTN), a matricellular protein, is increased in heart tissues of patients with HF. In the present study, we investigated whether a single injection of POSTN affects the electrophysiological properties in rat ventricles. After male Wistar rats were intravenously injected with recombinant rat POSTN (64 µg/kg, 24 hr), electrocardiogram (ECG) was recorded. Whole-cell patch clamp was performed to measure action potential (AP) and Na + current ( I Na ) in isolated ventricular myocytes. Protein expression of cardiac voltage-gated Na + channel (Na V 1.5) in isolated ventricles was examined by Western blotting. In ECG, POSTN-injection significantly increased RS height. POSTN-injection significantly delayed time to peak in AP and decreased I Na in the isolated ventricular myocytes. POSTN-injection decreased Na V 1.5 expression in the isolated ventricles. It was confirmed that POSTN (1 µg/ml, 24 hr) decreased I Na and Na V 1.5 protein expression in neonatal rat ventricular myocytes. This study for the first time demonstrated that a single injection of POSTN in rats decreased I Na by suppressing Na V 1.5 expression in the ventricular myocytes, which was accompanied by a prolongation of time to peak in AP and an increase of RS height in ECG.

[学科分类] 兽医学

[关键词] action potential;cardiac voltage-gated Na+ channel;electrocardiogram;Na+ current;periostin