【正文】
通道對離子大小的選擇性及電荷選擇性 ( 2)門控性 ( gating) 靜息態(tài);激活態(tài);失活態(tài) ( 3)通透性 ( permeation) 基本功能:產(chǎn)生細胞生物電現(xiàn)象,與細胞興奮性直接相關(guān)。1 Cardiovascular System Overview Pharmacological treatment of cardiovascular dysfunction is directed at pathologies affecting rhythm, cardiac contractile performance, blood vessel function, or blood pressure regulation. 2 Cardiac electrophysiology The electrical activity of each excitable cardiac cell can be measured as periodic changes in the electrical potential difference between the inside and outside of the cell. The polarity, amplitude, and pattern of change of this potential difference are determined by the transport of ions through highly regulated membrane proteins that form a variety of transporters and channels. Both passive and active transport mechanisms are involved. 3 心肌細胞膜電位離子基礎 0期:去極 快 Na內(nèi)流 1期:快速復極化期: K+ 外流 2期:緩慢復極化期(平臺期): Ca2+內(nèi)流, K+ 外流 3期:快速復極化末期: K+ 外流 4期:靜息期:排 Na+ 、 Ca2+,回攝 K+ 第 18章 作用于心血管系統(tǒng)離子通道的藥物 5 第一節(jié) .心血管系統(tǒng)離子通道 一 .離子通道研究簡史 電壓鉗:直接測定膜電流并分析電流的離子成分 Hodgkin amp。 研究離子通道的意義: 研究膜離子通道的通透機制及各種藥物選擇性作用于藥物的機制,對闡明: ?細胞生物電現(xiàn)象 (心電、腦電、肌電、胃腸電圖); ?疾病的發(fā)生原因; ?疾病的防治有重要意義。木藜蘆毒素 gray