Pathologies that result in early afterdepolarizations (EADs) are a known trigger for tachyarrhythmias, but the conditions that cause surrounding tissue to conduct or suppress EADs are poorly understood. Here we introduce a cell culture model of EAD propagation consisting of monolayers of cultured neonatal rat ventricular myocytes treated with anthopleurin-A (AP-A). AP-A-treated monolayers displ...

A B $ T R A C T Resting and action potentials were recorded from superfused strips of frog ventricle. Reducing the bathing calcium concentration ([Ca2+]0) with or without ethylene glycol-bis(~-aminoethyl ether)N,N,N',N'-tetraacetate (EGTA) prolongs the action potential (AP). The change in the duration of the AP extends over many minutes, but is rapidly reversed by restoring calcium ions. Other ...

Simultaneous recordings of contractile tension and transmembrane potentials from canine ventricular tissue yielded a consistent correlation of action potential (AP) alteration with contractile change associated with abrupt rate change. The AP terminating a relative prolongation of the cycle-length manifested shortening of phase 2 with lengthening of phase 3 and was associated with potentiation ...

Although oscillations in membrane potential are a prominent feature of sensory, motor, and cognitive function, their precise role in signal processing remains elusive. Here we show, using a combination of in vivo, in vitro, and theoretical approaches, that both synaptically and intrinsically generated membrane potential oscillations dramatically improve action potential (AP) precision by removi...

A B $ T R A C T Resting and action potentials were recorded from superfused strips of frog ventricle. Reducing the bathing calcium concentration ([Ca2+]0) with or without ethylene glycol-bis(~-aminoethyl ether)N,N,N',N'-tetraacetate (EGTA) prolongs the action potential (AP). The change in the duration of the AP extends over many minutes, but is rapidly reversed by restoring calcium ions. Other ...

A B $ T R A C T Resting and action potentials were recorded from superfused strips of frog ventricle. Reducing the bathing calcium concentration ([Ca2+]0) with or without ethylene glycol-bis(~-aminoethyl ether)N,N,N',N'-tetraacetate (EGTA) prolongs the action potential (AP). The change in the duration of the AP extends over many minutes, but is rapidly reversed by restoring calcium ions. Other ...

Introduction The evidence of an inflammatory status at onset psychosis supports the adjunction anti-inflammatory agent to antipsychotic (AP). Some negative results these clinical trials lead us wonder about power AP. Objectives Would action associated agents be negligible compared potential AP? Methods We conducted a prospective study. included patients hospitalized for acute relapse schizophre...

BACKGROUND AND PURPOSE Action potential (AP) recordings in ex vivo heart preparations constitute an important component of the preclinical cardiac safety assessment according to the ICH S7B guideline. Most AP measurement models are sensitive, predictive and informative but suffer from a low throughput. Here, effects of selected anti-arrhythmics (flecainide, quinidine, atenolol, sotalol, dofetil...

In cardiac-specific Na(+)-Ca(2+) exchanger (NCX) knockout (KO) mice, the ventricular action potential (AP) is shortened. The shortening of the AP, as well as a decrease of the L-type Ca(2+) current (I(Ca)), provides a critical mechanism for the maintenance of Ca(2+) homeostasis and contractility in the absence of NCX (Pott C, Philipson KD, Goldhaber JI. Excitation-contraction coupling in Na(+)-...

The effects of two SCN5A mutations (Y1795C, Y1795H), previously identified in one Long QT syndrome type 3 (LQT3) and one Brugada syndrome (BrS) families, were investigated by means of numerical modeling of ventricular action potential (AP). A Markov model capable of reproducing a wild-type as well as a mutant sodium current (I(Na)) was identified and was included into the Luo-Rudy ventricular c...