摘要
氟对心肌细胞电、机械活动都有明显的作用。可使其动作电位振幅(APA)、零相最大上升速率(V_(max))及动作电位超射幅度降低;动作电位时程(APD)缩短;有效不应期(ERP)先缩短而后延长。在一定剂量时,氟表现出正性肌力作用,可使心室肌收缩力增强1至数倍,但随着剂量增加又可表现出负性肌力作用,直至收缩力消失。单剂量时也表现出一定的时间依从性。
it was obvious that the effects of fluorine (F) on electro-mechanical activities of myocardium. F 10～150 ppm decreased the action potential amplitude (APA), the maximum depola rization of o phase (V_(max)) and the overshoot of action potential (OS) , and shortened the action potential duration (APD). The effective refractory period (ERP) was shortened by F at early stage but prolonged at a later time. F has a positive inotropic action at certain dosages, the contractile force of ventricular muscles was increased by one to several times as compared with that of control; but with the increasing of dosage of F, the posit ive inotropic action become to negative or disapp eared, it was showed that the positive inotropic action of F was time-dependent at a single dosage.
关键词
氟
心肌细胞
动作电位
收缩力
Fulorine
myoeardial cells, action Potential, contractile fcrce
