第一节心脏的生物电现象及节律性 兴奋的产生与传导 心肌组织的生理特性兴奋性传导性自律性收缩性 心肌细胞的分类: 工作细胞(普通心肌):心房肌细胞,心室肌细胞 自律细胞(特殊传导系统)起搏(P)细胞,浦肯野细胞 二种细胞的比较: 兴奋性传导性自律性收缩性 工作细胞 有有无 自律细胞 有有有无
第一·节 心脏的生物电现象及节律性 兴奋的产生与传导 心肌组织的生理特性：兴奋性 传导性 自律性 收缩性 心肌细胞的分类： 工作细胞（普通心肌）：心房肌细胞，心室肌细胞 自律细胞（特殊传导系统）：起搏（Ｐ）细胞，浦肯野细胞 二种细胞的比较: 兴奋性 传导性 自律性 收缩性 工作细胞 有 有 无 有 自律细胞 有 有 有 无
Electrical Activity of the heart OBJECTIVES Explain the types of cardiac action potentials. Define the ionic basis of cardiac action potentials. Explain the temporal changes in cardiac excita bility 心肌细胞的快反应动作电位和慢反应动作电位; 心肌细胞的电生理特性(传导性和兴奋性)
Electrical Activity of the Heart OBJECTIVES • Explain the types of cardiac action potentials. • Define the ionic basis of cardiac action potentials. • Explain the temporal changes in cardiac excitability. • 心肌细胞的快反应动作电位和慢反应动作电位； • 心肌细胞的电生理特性（传导性和兴奋性）
威廉.艾因特霍芬 (Willem einthoven) 荷兰生理学家威廉.艾因特霍芬 ( Willem einthoven,1860~1927)因对 心电图学的开创性工作和无与伦比的贡 献而被誉为“心电图之父”,并于1924 年获诺贝尔生理学或医学奖。 Willem einthoven
Willem Einthoven 威廉 . 艾因特霍芬 （Willem Einthoven） 荷兰生理学家威廉 . 艾因特霍芬 （ Willem Einthoven, 1860~1927 ） 因对 心电图学 的 开创性工作和无与伦比的贡 献 而 被誉为“心电图之父”，并于1924 年获 诺贝尔生理学或医学奖
Cardiac Transmembrane Potentials are Prolonged The electrical behavior of -SAN (005) cardiac cells differs considerably AM (0.4) from that of nerve cells or of AVN (002) smooth or skeletal muscle ceils in (0.2) general, the durations of action potentials are much longer in (20) cardiac cells than in nerve cells or (40) in smooth or skeletal muscle cells VM (10) The action potentials differ 0300600 substantially among various 时间(ms) type of cardiac cells depending 图4-5心脏各部分心肌细胞的 跨膜电位和兴奋传导速度 on the function and location of sAN:窦房结AM:心房肌AMN:结区BH1希氏束 PF:浦肯野纤维TPF末梢浦肯野纤维VM:心室肌 those cells 传导速度单位m/s
Cardiac Transmembrane Potentials are Prolonged The action potentials differ substantially among various type of cardiac cells depending on the function and location of those cells. The electrical behavior of cardiac cells differs considerably from that of nerve cells or of smooth or skeletal muscle ceils. in general, the durations of action potentials are much longer in cardiac cells than in nerve cells or in smooth or skeletal muscle cells
he potential charge recorded from ventricular muscle cell Resting potential -90 mv (interior is lower than that of the surrounding medium) Action potential Phase: the rapid upstroke of the action potential depolarizes from -90mv to +2030 mV; Phase 1: a brief period of partial repolarization Fast response +20mV→>0mV, Phase 2:a plateau( persists for about 0. 2 second).ao 3 It is main difference 80 comparing with nerve and skeleton muscle cells 120 0100200300
Action potential: Phase 0 : the rapid upstroke of the action potential. depolarizes from -90mV to +20～30 mV; Phase 1 ：a brief period of partial repolarization +20 mV → 0 mV, Phase 2 ：a plateau ( persists for about 0.2 second). the potential charge recorded from ventricular muscle cell Resting potential ： - 90 mV (interior is lower than that of the surrounding medium) It is main difference comparing with nerve and skeleton muscle cells