Vliv antiarytmika ajmalinu na elektrofyziologické vlastnosti srdeční buňky pracovního myokardu
| Title in English | Effect of antiarrhythmic drug ajmaline on electrophysiological properties of cardiac cell of working myocardium |
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| Year of publication | 2005 |
| MU Faculty or unit | |
| Citation | |
| Description | Ajmaline induced a decrease of maximum velocity of the fast depolarization, a decline of the amplitude and a prolongation of action potential. Ajmaline inhibited all the main ionic membrane currents. The efficacy of ajmaline declined in the subsequent order: sodium current INa (27,8 micromol/l) and transient outward potassium current Ito (25,9 micromol/l) – IK,end, the potassium current measured at the end of 250ms-impulse that is mainly composed of IK (61,0 micromol/l) – ICa-L, the L-type calcium current (70,8 micromol/l) – inward moiety of potassium current IK1 (only 36 % block in the presence of 300 micromol/l ajmaline). Ajmaline is also very effective inhibitor of the potassium current sensitive to ATP IK(ATP) (13,3 micromol/l). Inhibition of INa and Ito induced by ajmaline was frequency-independent in the range between 20 and 200 min-1 in contrast to the propafenone-induced inhibition (another class I antiarrhythmic drug). |
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