HCN Channels And Regulation Of Receptor Expression In Atrial Fibrillation In Patients With Atrial

Objective: To evaluate the gene expression and protein expression of atrialhyperpolarization-activated cyclic nucleotide-gated channel (HCN) informs and5-hydroxytryptamine4receptor in patients of AF associate with valvular heart disease.Methods: The left atrial tissue were obtained from86patients with valvular heart diseasewho underwent cardiac valve replacement.38patients were sinus rhythm,48patients werechronic atrial fibrillation.The mRNA level of HCN and5-HT4-R were measured byReal-time quantitative polymerase chain reaction (Real-time PCR) and protein expressionby western blot. And45patients were rheumatic cardiac valve heart disease.Cardiacfunction according to different circumstances will be different in patients with cardiacreclassified as rheumatic heart disease and atrial fibrillation with heart failure and normalcardiac functionin patients withrheumatic heart disease and atrial fibrillation groups.Results: Compared to sinus rhythm group, the mRNA and protein expression of HCN2and HCN4were increased in AF group, but5-HT4-R was versa.The mRNA and proteinexpressionof HCN1was slightly higherin AF group, but the differences were notstatistically significant.The mRNA of HCN2was positive correlated with the left atrialdimension. The mRNA of5-HT4-R was negative correlated with the left atrial dimension.HCN4in atrial fibrillation associated with heart disease, heart failure and normal cardiacfunction in patients with rheumatic heart valve disease in patients with atrial fibrillationwere expressed, but rheumatic heart disease and heart failure patients with atrialfibrillation in the mRNA levels and protein expression levels compared with normalcardiac function in patients with rheumatic heart disease and atrial fibrillation wassignificantly highter. Conclusion: The increased of mRNA and protein expression level ofHCN2and HCN4may be very important molecular mechanism in patients with atrialfibrillation (AF), which the changes in patients with valvular heart disease were associatedwith electrical remodeling. HCN2and5-HT4-R expression changes caused byleft atrial fibrillation diameter increase is considered to be an important factor in atrialfibrillation-prone and maintain.HCN4is the predominant channel subtype AF withvalvular heart disease of normal human heart, and its expression is further amplified byfailing heart. HCN4up-regulation may play a role in atrial arrhythmogenesis with valvularheart disease of heart failing human.