Cardioprotective effects of simvastatin on reversing electrical remodeling induced by myocardial ischemia-reperfusion in normocholesterolemic rabbits.

Background: Recent studies have revealed that pretreatment with statin is effective in preventing arrhythmia, but its electrophysiological mechanism is unclear. This study was conducted to investigate the cardioprotective effects of simvastatin on reversing electrical remodeling in left ventricular myocytes of rabbit heart undergoing ischemia-reperfusion, so as to explore the ionic mechanism responsible for the anti-arrhythmic effect of statin.

Methods: Forty-five rabbits were randomly divided into three groups: ischemic-reperfusion group (I-R), simvastatin intervention group (Statin) and sham-operated control group (CON).

[Effect of simulated ischemia on activity and heterogeneity of Na+ channel in rabbit ventricular epicardial, midmyocardial and endocardial myocytes].

Objective: To study the ionic mechanism of reentrant arrhythmia.

Methods: Single myocytes were enzymatically isolated from the epicardium, midmyocardium and endocardium of the left ventricle free wall of rabbit, followed by whole-cell patch-clamp recording of the Na(+) current (I(Na)) of the 3 cellular subtypes (superfused with normal and then simulated ischemia solution). The currents in the 3 cellular subtypes before and after simulated ischemia lasting for 10, 20, and 30 min, respectively, were compared.