The Changes of Gene Expression and Protein Level of Stretch-Activated Chloride Channel in Atrial Myocardium of Dogs with Atrial Fibrillation

Introduction: ICl,stretch have been reported to be involved in the development of atrial fibrillation, so we observed the changes of transcription and translation levels of ICl,stretch in isolated atrial myocardium of heart failure canine models. Material and methods: In the control group (N = 10), five dogs were untreated and the other five received sham operation, while dogs in the heart failure group (N = 10) were implanted with cardiac pacemakers and underwent right ventricular pacing to induce heart failure. Cardiac structure and function were evaluated. The gene expression and protein level of ICl,stretch in the left atrial appendage were detected. Results: The left atrial diameter, right atrial dimension, left ventricular diastolic dimension, and right ventricular diastolic dimension were significantly larger in the heart failure group (P < 0.05). In contrast, the ejection fraction and the left ventricular shorten fraction were higher in the control group (P < 0.05). Both the mRNA and protein expression levels of ICl,stretch in atrial myocardium of the heart failure group were significantly higher compared with the control group. Conclusion: ICl,stretch might play an important role in the vulnerability to atrial fibrillation in dilated atria with heart failure and could be a potential therapeutic target for atrial fibrillation.