增龄性心房颤动心房肌钙转运调控蛋白表达改变的实验研究

Objective: This study is to investigate whether or not the dysfunction of atrial repolarization and abnormality of intracellular Ca2+ handling protein augment with aging, creating a substrate for initiation and maintenance of atrial fibrillation (AF). Methods: Four groups of dogs were studied: adult and old dogs in sinus rhythm (SR) and with chronic AF (CAF) induced by rapid atrial pacing. The mRNA and protein expressions of Ca2+ handling protein were measured by real-time qRT-PCR and Western-blot methods. Results: Compared to adult group, the mRNA and protein expressions of of L-type calcium channel a1c was decreased, whereas the expressions of calcium adenosine triphosphatase was increased; moreover, compared to SR groups, the expressions of intracellular Ca2+riphosphatase was increased; moreover, compared to SR groups, the expressions of intracellular Ca2+ handling protein except phospholamban was significantly decreased in both adult and aged groups specifically in the latter with AF (all P < 0.05). Conclusions: These aging-induced electrophysiological and molecular changes specifically in the incidence of AF showed that pathophysiological adaptations might be important in the old for both AF initiation during SR and subsequent stabilization of AF.