摘要
目的探讨乙酰胆碱(ACh)对人心房肌的脱敏作用及其机制。方法取30例心脏手术患者的右心耳,部分用酶解法分离成单细胞,分别应用标准微电极技术、肌力换能器和全细胞膜片钳技术记录组织动作电位、心肌收缩力和单细胞乙酰胆碱敏感钾电流(IK,ACh),并观察乙酰胆碱的作用。结果10μmol/L乙酰胆碱可降低心房肌收缩力,缩短动作电位时程,随着时间推移效应逐步减小,即出现脱敏现象。乙酰胆碱敏感钾电流(IK,ACh)出现类似的脱敏现象。结论ACh降低心房肌组织收缩力的作用有脱敏现象,脱敏的发生可能与心房肌细胞动作电位时程(APD)的脱敏及IK,ACh的脱敏有关。
Objective To investigate the desensitization of acetyleholine （ACh） on human atrial myocardium and its mechanism. Methods The contraction force was recorded by force transducer, parameters of action potential （AP） in human atrial fibers by using standard intracellular microelectrode technique, and the IK. Achby using whole cell patch clamp. Results ACh （10μmol/L） could inhibit the action potential for several rain. After the recovery of the action potential, the resting potential was decreased and the action potential duration （APD） shortened as well. The desensitization was found in the contraction force, APD and IK. ACh. Conclusion The decrease in contraction of the atrial muscles by ACh showed desensitization phenomenon, which might be related with the desensitization of action potential and that of IK. ACh in the atrial muscles.
出处
《华中科技大学学报（医学版）》
CAS
CSCD
北大核心
2008年第6期805-807,811,共4页
Acta Medicinae Universitatis Scientiae et Technologiae Huazhong
基金
国家自然科学基金资助项目(No.30570729)
湖北省卫生厅科研基金资助项目(No.JX3B08)
