1、田野 教授哈医大二院心内科兴奋 收 缩 耦 联 和心力衰竭的治疗TOPICSp Excitation-contraction (EC) coupling Excitation Calcium Cycling Contractionp Alterations of E-C coupling in HFp Inotropic agents for HFExcitation-contraction coupling “The power of locomotion is that which contracts and relaxes the muscles whereby the members
2、and joints are moved, extended or flexed. This power reaches the limbs by way of the nerves and there are as many forms of power as there are of movement. Each muscle has its own peculiar purpose and it obeys the decree of the composite sense.“ Avicenna(11671248)William Harvey (1578 1657) He was an
3、English medical doctor /physician, who is credited with being the first to correctly describe, in exact detail, the systemic circulation and properties of blood being pumped around the body by the heart. We shall designate the entire seque-nce of reactions: excitation, inward acting link, and activa
4、tion of contra-ction by the term excitation-contraction coupling.ALEXANDER SANDOW,1952(New York University)Sandow A.Yale J Biol Med . 1952.25 (3): 176201 Cardiac excitationcontraction coupling is the process from electrical excitation of the myocyte to contraction of the heart (which propels blood o
5、ut). The ubiquitous second messenger Ca2+ is essential in cardiac electrical activity and is the direct activator of the myofilaments, which cause contraction.Bers DM. Nature, 2002, 415(6868): 198-205.Excitation The cardiac action potential A notable difference between skeletal and cardiac myocytes is how each elevates the myoplasmic Ca2+ to induce contraction. In cardiac myocytes, the release of Ca2+ from the sarcoplasmic reticulum is induced by Ca2+ influx into the cell through voltage-gated calcium channels. Calcium Cycling