Negative Chronotropic Effects of Class I Antiarrhythmic Drugs on Guinea Pig Right Atria: Correlation with L-Type Ca2+ Channel Blockade
نویسندگان
چکیده
The negative chronotropic effects of eight Vaughan Williams Class I antiarrhythmic drugs were examined in guinea pig right atrial tissue preparations. decreased the spontaneous beating rate at concentrations overlapping with their therapeutic blood levels. Cibenzoline, aprindine, flecainide, and propafenone showed stronger effects; 10 µM each drug to about 75% initial values. Disopyramide, mexiletine, pilsicainide, ranolazine weaker 90% potency correlated reported IC50 values block L-type Ca2+ channel current rather than Na+ K+ currents. for blockade hyperpolarization-activated inward (If) Na+-Ca2+ exchanger much higher those current. These results indicate that can be largely explained by channel.
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ژورنال
عنوان ژورنال: J
سال: 2023
ISSN: ['2571-8800']
DOI: https://doi.org/10.3390/j6010008