Potassium channels are trans-membrane proteins, which selectively transport K+ ions across cell membranes and play a key role in regulating the physiology of excitability cells and signal transduction pathways. Bothutous Schach (BS) scorpion venom consists of several polypeptides that could modulate ion channels. In this study, the effects of BS crude venom on passive and active electrophysiolo...

The outward-going rectification was examined in crab muscle fibres under current clamp and voltage clamp conditions. Experiments were performed on large diameter crab muscle fibres; these generate all-or-none responses. Under current clamp conditions, the outward-going rectification can be elicited in the muscle membrane in a choline chloride solution; it however disappears in CT free artificia...

During growth or degeneration neuronal surface area can change dramatically. Measurements of membrane protein concentration, as in ion channel or ionic conductance density, are often normalized by membrane capacitance, which is proportional to the surface area, to express changes independently from cell surface variations. Several electrophysiological protocols are used to measure cell capacita...

Patch clamping is a gold-standard electrophysiology technique that has the temporal resolution and signal-to-noise ratio capable of reporting single ion channel currents, as well as electrical activity of excitable single cells. Despite its usefulness and decades of development, the amplifiers required for patch clamping are expensive and bulky. This has limited the scalability and throughput o...

When current clamped, skate electroreceptor epithelium produces large action potentials in response to stimuli that depolarize the lumenal faces of the receptor cells. With increasing stimulus strength these action potentials become prolonged. When the peak voltage exceeds about 140 mV the repolarizing phase is blocked until the end of the stimulus. Perfusion experiments show that the rising ph...