Gender dependent differences in molecular electrophysiological targets in failing and nonfailing human hearts

Previous epidemiological studies have shown that males tend to have an increased overall lifetime risk of developing atrial fibrillation (AF), whereas females tend to be more susceptible to the development of ventricular tachyarrhythmias resulting from long-QT syndrome and drug-induced Torsades de Pointes. In this study, we compared the transcript-level expression of 89 ion channel subunits, calcium handling proteins, and other transcription factors in the left atria (LA) and ventricles (LV) of human hearts of both genders. Total RNA from the LA and LV of failing male (n=9), failing female (n=7), nonfailing male (n=9), and nonfailing female (n=9) hearts was probed using a custom-designed Taqman gene array from Applied Biosystems. Tissues from LA (n=22), LV (n=22), LV endocardium (n=12), and LV epicardium (n=12) were analyzed by the Applied Biosystems SDS 2.3 software using the threshold cycle (Ct) relative quantification method with GAPDH as an endogenous control.