Shensong Yangxin capsules prevent ischemic arrhythmias by prolonging action potentials and alleviating Ca2+ overload

Abstract

Shensong Yangxin capsules (SSYX) are an effective traditional Chinese medicine that has been used to treat coronary heart disease clinically. The present study aimed to establish whether SSYX prevent ischemic arrhythmias in rats, and to explore the underlying mechanisms. Male rats were pretreated with distilled water, SSYX and amiodarone for one week. Acute myocardial ischemia (AMI) was performed to induce ischemic arrhythmias. The incidence and severity of ischemic arrhythmias were evaluated. The action potential, transient outward K+ current (Ito) and inward rectifier K+ current (IK1) of rat cardiomyocytes were measured using the patch‑clamp technique. The intracellular Ca2+ concentration of the cardiomyocytes was measured using a laser scanning confocal microscope. The results revealed that SSYX lowered the incidence of arrhythmia markedly during AMI. Furthermore, SSYX delayed the appearance, and reduced the severity, of ischemic arrhythmias compared with the control. In addition, SSYX markedly decreased the ratio of the myocardial infarction region to the whole heart. In an in vitro study, SSYX prolonged the action potential duration of rat cardiomyocytes, and inhibited Ito and IK1 markedly. Additionally, SSYX inhibited Ca2+ elevation induced by KCl in cardiomyocytes. These results suggested that SSYX prevents ischemic arrhythmia, and the underlying mechanism responsible for this process may include prolonging the action potential and alleviating Ca2+ overload.

Acute Efficacy of a Traditional Chinese Medicine for Treatment of Frequent Premature Ventricular Contractions in Patients with Concomitant Sinus Bradycardia: Results from a Double-Blind, Placebo-Controlled, Multicentre, Randomized Clinical Trial

“…Patch-clamping of isolated ventricular myocytes has demonstrated that SSYX is a multichannel blocker with measurable effects on the fast sodium, L-type calcium channel, transient outward potassium (Ito), and inward rectifier potassium currents (IKr), resulting in an overall prolongation of the action potential [10, 11]. Similarly to our findings, sinus rates are increased with SSYX, although this increase is abolished with autonomic blockage with metoprolol and atropine [12].…”

Increased Piezo1 channel activity in interstitial Cajal-like cells induces bladder hyperactivity by functionally interacting with NCX1 in rats with cyclophosphamide-induced cystitis

“…In our previous research, we demonstrated that bladder ICC-LC hyperactivity accounted for bladder hyperactivity in CYP-induced chronic cystitis, which was characterized by excessive Ca 2+ entry into cells upon carbachol application 12 . Furthermore, Ca 2+ overload in cardiomyocytes is closely related to cardiac dysfunction 37 , 38 . Thus, we suggest that abnormal Ca 2+ signaling in bladder ICC-LCs may be involved in the pathogenesis of bladder dysfunction.…”

Shensong Yangxin Protects Against Metabolic Syndrome-Induced Ventricular Arrhythmias by Inhibiting Electrical Remodeling

“…Previous study reported that SSYX could reverse atrial electrical remodeling and the atrial fibrillation by adjusting the autonomic nerve activity and inhibiting atrial inflammation ( Zhao et al., 2017 ). Another study reported that SSYX could reduce acute myocardial ischemia (AMI)-induced VA by inhibiting transient outward K + current ( I to ) and reducing intracellular Ca 2+ concentration of the cardiomyocytes ( Zhao et al., 2016 ). Although SSYX may exert anti-arrhythmia effect by reversing electrical remodeling, until now, the role of SSYX in the setting of MetS-induced VA remains unclear.…”