Publications by authors named "Alexander C Schneck"
Effects of the chromanol HMR 1556 on potassium currents in atrial myocytes.
Naunyn Schmiedebergs Arch Pharmacol
March 2003
Purpose: The chromanol HMR 1556 is a potent blocker of KvLQT1/minK potassium channels expressed in Xenopus oocytes. The compound is therefore a new class III antiarrhythmic drug with a distinct mechanism of action. However, the effect of HMR 1556 on atrial ion channels and the selectivity of block in the human heart has not been investigated.
View Article and Find Full Text PDFArticle Synopsis
- The slow component of the delayed rectifier potassium current (I(Ks)) in the heart is strongly regulated by beta-adrenergic receptors, particularly by catecholamines like isoproterenol, though the opposing functions of beta(1) and beta(3) receptors on I(Ks) are not fully understood.
- Using patch-clamp techniques on guinea-pig ventricular myocytes, researchers found that isoproterenol significantly increases I(Ks) but does so differently when beta(1) and beta(2) receptors are blocked, leading to a decrease in current amplitude instead.
- The beta(3)-adrenoceptor appears to play a significant role in modulating I(Ks) and overall cardiac action potentials, suggesting its