AIMS Present study was performed to compare the dynamics of human L-type calcium current (ICa,L) flowing during rectangular voltage pulses, voltage ramps, and action potentials (APs) recorded from epicardiac and endocardiac canine ventricular cells. METHODS ICa,L was recorded in single myocytes isolated from undiseased human hearts using the whole cell voltage clamp technique. RESULTS The d...

Electrostatic discharge (ESD) from charged dielectric materials used within explosive environments presents a significant hazard. To investigate dielectric surface charging, and methods of removing the charge, in detail and in a controlled way, a test stand has been built and utilized to study the behavior of several common dielectric materials used in such environments. A corona discharge sour...

Ionic (Ii) and gating currents (Ig) from noninactivating Shaker H4 K+ channels were recorded with the cut-open oocyte voltage clamp and macropatch techniques. Steady state and kinetic properties were studied in the temperature range 2-22 degreesC. The time course of Ii elicited by large depolarizations consists of an initial delay followed by an exponential rise with two kinetic components. The...

Slow Inward Current, Thallium Intoxication, Voltage Clamp, Available Intracellular Energy To conclude our investigation of thallium effects on cardiac tissues, we studied the slow inward current of sheep cardiac Purkinje fibres exposed to 10“7 to 105 m Tl+ for extended periods of up to 80 min. Our previous results had suggested a possible involvement of the slow inward current during thallium i...

Voltage-gated calcium channels contain four highly conserved transmembrane helices known as S4 segments that exhibit a positively charged residue every third position, and play the role of voltage sensing. Nonetheless, the activation range between high-voltage (HVA) and low-voltage (LVA) activated calcium channels is around 30-40 mV apart, despite the high level of amino acid similarity within ...

Electrophysiological recordings of outside-out patches to fast-flow applications of glycine were made on patches derived from the Mauthner cells of the 50-h-old zebrafish larva. As for glycinergic miniature inhibitory postsynaptic currents (mIPSCs), depolarizing the patch produced a broadening of the transient outside-out current evoked by short applications (1 ms) of a saturating concentration...

Neuronal voltage-gated calcium channels provide a pathway for calcium influx that is required for processes ranging from intracellular signaling to alterations in cellular excitability. In hippocampal neurons, we have characterized a subtype of dihydropyridine-sensitive L-type calcium channels (Lp channel) that shows multiple kinds of voltage-dependent potentiation of its activity. One type of ...