Unique Molecular Profile of Transient Outward Potassium Current (Ito) Subunits in Cardiac Purkinje Fibers
نویسندگان
چکیده
منابع مشابه
Influence of chloride, potassium, and tetraethylammonium on the early outward current of sheep cardiac Purkinje fibers
In voltage clamp studies of cardiac Purkinje fibers, a large early outward current is consistently observed during depolarizations to voltages more positive than -20 mV. After the outward peak of the current, the total membrane current declines slowly. Dudel et al. (1967. Pfluegers Arch. Eur. J. Physiol. 294:197--212) reduced the extracellular chloride concentration and found that the outward p...
متن کاملUnique cardiac Purkinje fiber transient outward current β-subunit composition: a potential molecular link to idiopathic ventricular fibrillation.
RATIONALE A chromosomal haplotype producing cardiac overexpression of dipeptidyl peptidase-like protein-6 (DPP6) causes familial idiopathic ventricular fibrillation. The molecular basis of transient outward current (I(to)) in Purkinje fibers (PFs) is poorly understood. We hypothesized that DPP6 contributes to PF I(to) and that its overexpression might specifically alter PF I(to) properties and ...
متن کاملTransient outward potassium current in ICC.
Interstitial cells of Cajal (ICC) are the pacemakers of the gut, initiating slow-wave activity. Several ion channels have been identified that contribute to the depolarization phase of the slow wave. Our aim was to contribute to knowledge about the identity and role of ICC potassium channels in pacemaking. Here we describe a transient outward potassium current in cell-attached patches of ICC. T...
متن کاملBlock of outward current in cardiac purkinje fibers by injection of quaternary ammonium ions
We have studied the effects of iontophoretic injection of the quaternary ammonium compounds tetraethylammonium (TEA) and tetrabutylammonium (TBA) in cardiac purkinje fibers. We find that TBA(+) is a more effective blocker than TEA(+), but injection of either compound reduces the time-dependent outward plateau currents, transient outward current (I(to)), and the delayed rectifier (I(x)). Our fin...
متن کاملDistinct Transient Outward Potassium Current (Ito) Phenotypes and Distribution of Fast-inactivating Potassium Channel Alpha Subunits in Ferret Left Ventricular Myocytes
The biophysical characteristics and alpha subunits underlying calcium-independent transient outward potassium current (Ito) phenotypes expressed in ferret left ventricular epicardial (LV epi) and endocardial (LV endo) myocytes were analyzed using patch clamp, fluorescent in situ hybridization (FISH), and immunofluorescent (IF) techniques. Two distinct Ito phenotypes were measured (21-22 degrees...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Biophysical Journal
سال: 2010
ISSN: 0006-3495
DOI: 10.1016/j.bpj.2009.12.1819