中文摘要：

目的 从蛋白质组学角度分析心房颤动（房颤）患者心房能量代谢状态,揭示房颤的发生基质.方法 2011年1月至8月于中南大学湘雅二医院获取患二尖瓣疾病需行外科换瓣手术的窦性心律患者（n=6）和房颤患者（n=8）左心耳组织.分离蛋白质,行同重元素标记的相对和绝对定量（iTRAQ）标记及质谱分析,通过分析软件行蛋白质鉴定和定量分析,运用蛋白印迹法分析确定结果准确性.结果 发现1 023个蛋白质,517个差异表达蛋白质,122个能量代谢相关,46个参与呼吸链过程.下调蛋白质在慢性房颤患者左心耳组织的能量代谢中占据主导优势.蛋白印迹分析证实了结果的可靠性.结论 瓣膜性心脏病患者慢性房颤过程心房肌细胞产能状态受损.

英文摘要：

Objective Significant modifications in cardiac energy metabolism during atrial fibrillation （AF） were demonstrated in previous studies which suggested a closely relationship between AF and cardiac energy metabolism.The objective of our study was to analyze the expression profiles of respiratory chain related proteins in atrial appendages from AF patients and provide a better understanding of the mechanisms of AF.Methods Left atrial appendages（LAA） were obtained at Second Xiangya Hospital,Central South University from January to August 2011.We used isobaric tag for relative and absolute guantitation （iTRAQ）-coupled 2-D LC-MS/MS technique to screen the expression profiles of the respiratory chain related proteins in LAA from patients both in sinus rhythm （SR,n =6） and in AF （n =8）.Specimens were pulverized and homogenized in a lysate buffer,then digested by trypsin and labeled with different iTRAQ tags.The pooled labeled peptides were analyzed by liquid chromatography tandem mass spectrometry （LC-MS/MS）.Protein identification and relative iTRAQ quantification were performed with the ProteinPilot Software 4.0.Protein differentially expression were validated by Western blot analysis to verify the results obtained by iTRAQ proteomic studies.Results Data from iTRAQ labeling and LC-MS/MS technique showed 1 023 unique proteins from the cardiac tissues,517 differentially expressed proteins.Meanwhile,we identified 122 differential expressed proteins closely related to energy metabolism.Among those proteins,46 of them were related to respiratory chain.The down-regulated proteins were mainly involved in energy metabolism.Western blotting further validated the content of three differently expressed proteins between LAA from patients with mitral valve disease in SR and in permanent AF and also validated the reliability of the iTRAQ proteomic studies used in cardiac tissue.Conclusion Most of the respiratory chain related proteins in the LAA of AF patients were down-regulated indicating the energy product