Academic Journal
Quinidine delays IK activation in guinea pig ventricular myocytes.
| العنوان: | Quinidine delays IK activation in guinea pig ventricular myocytes. |
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| المؤلفون: | Roden, D M, Bennett, P B, Snyders, D J, Balser, J R, Hondeghem, L M |
| المصدر: | Circulation Research ; volume 62, issue 5, page 1055-1058 ; ISSN 0009-7330 1524-4571 |
| بيانات النشر: | Ovid Technologies (Wolters Kluwer Health) |
| سنة النشر: | 1988 |
| الوصف: | A major action of the antiarrhythmic agent quinidine is prolongation of cardiac repolarization. In these experiments, the time-dependent effects of quinidine on the delayed rectifier potassium current, IK, a current contributing to cardiac repolarization, were investigated in acutely disaggregated guinea pig ventricular myocytes using the whole-cell recording configuration of the patch-clamp method. The effect of quinidine on IK was dependent on the duration of depolarization. After long (2,000 msec) pulses, IK was reduced by 30 +/- 27% (SD; n = 8, paired) by 10 microM quinidine; in contrast, after short (100 msec) pulses, the drug decreased IK 65 +/- 35% (p less than 0.05). This effect was found both in paired experiments as well as when quinidine-pretreated cells were compared to non-pretreated cells. Quinidine significantly delayed IK activation (9 +/- 20 msec at baseline vs. 44 +/- 25 msec in drug, p less than 0.05), but did not alter the subsequent time course of activation (time constant 659 +/- 118 msec). These findings are consistent with the hypothesis that quinidine promotes occupancy of a channel state from which opening does not occur. |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| DOI: | 10.1161/01.res.62.5.1055 |
| DOI: | 10.1161/01.RES.62.5.1055 |
| الاتاحة: | http://dx.doi.org/10.1161/01.res.62.5.1055 https://www.ahajournals.org/doi/pdf/10.1161/01.RES.62.5.1055 |
| رقم الانضمام: | edsbas.B1689A08 |
| قاعدة البيانات: | BASE |
| DOI: | 10.1161/01.res.62.5.1055 |
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