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.docVIP

 n 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# 许国军，甘天翊，周贤惠，汤宝鹏，李耀东，姜涛** 5 10 15 （新疆医科大学第一附属医院心脏中心，乌鲁木齐 830000） 摘要：本研究目的是为论证是否存在心房肌细胞膜 L-型钙通道蛋白和细胞内肌质网钙转运 调控蛋白异常表达伴随增龄而显现，致使心肌细胞内钙稳态遭到破坏，以期阐明增龄性房颤 心房电重构的分子基质。方法：通过持续快速心房起搏建立慢性房颤犬模型，采用 qRT-PCR 和 Western-blot 方法检测 4 组犬（成年和老年窦性心律犬、成年和老年慢性房颤犬）左心房 肌钙转运调控蛋白在 mRNA 和蛋白质表达水平变化。结果：与成年犬比较，老年犬心电图 P 波持续时间显著地延长，P 波离散度显著地增大，在 mRNA 和蛋白质表达水平均，老年 犬左心房肌 LVDCCa1c 显著地降低，而 Ca2+-ATPase 显著地升高(均 P0.05)，RYR2, IP3R1 和 PLN 普遍地显示出上调的趋势，但无统计学差异(P＞0.05)；与窦性心律犬比较，房颤犬 除受磷蛋白（PLN）之外， LVDCCa1c 和肌浆网钙转运调控蛋白均显著地下调，尤其是老 年房颤犬这种下调趋势更加明显(P0.05)。结论：这种伴随增龄与房颤而显现的左房电生理 和钙转运调控蛋白特异性改变（适应与不良适应反应）可能是增龄性房颤心房电重构的分子 基质。 关键词：心房颤动；增龄；L-型钙通道；钙转运调控蛋白；基因表达 中图分类号：R541.7 20 Age-related alterations in calcium handling protein in dog with chronic atrial fibrillation XU Guojun, GAN Tianyi, ZHOU Xianhui, TANG Baopeng, LI Yaodong, JIANG Tao (Department of Cardiology, First Affiliated Hospital, Xinjiang Medical University, Urumqi 25 30 35 40 830000) Abstract: 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 P0.05). Conclusions: These aging-induced el