We implemented a simple feedback system that modifies the conventional current clamp mode of a patch clamp amplifier so that transient potentials, such as action potentials and synaptic potentials, can be measured as in the usual current clamp, while the average membrane potential is kept constant at a value chosen by the user. The circuit thus works like the current clamp for high frequency si...

introduction: some dental sealers have neurotoxic effects on neuronaltissues. these effects appear to be mediated through the inhibition of ionic channels. intracellular recording was performed on neuronal cells tocharacterize the underlying ionic mechanisms of neurotoxicity induced by roth 801. materials and methods: experiments were carried out on f1 neuronal soma membrane located in the righ...

introduction: pentylenetetrazol (ptz) is one of the most often used epileptogenic agents. several effects of this epileptogenic drug have been described, but the mechanism of the epileptogenic action of ptz at the cellular level is still unclear. in this study the effect of ptz, on the ionic currents of d5 neuronal soma membrane in helixaspersa, using intracellular recording technique was inves...

In these experiments we have investigated the feasibility and accuracy of recording steady-state and dynamic changes in transmembrane potential noninvasively across an intact cell-attached patch using the current-clamp mode of a conventional patch-clamp amplifier. Using an equivalent circuit mimicking simultaneous whole-cell voltage-clamp and cell-attached current-clamp recordings we have defin...

Ion channels are responsible for control of cell function in excitable tissues such as heart and brain and also in organs and tissues traditionally thought to be non- excitable including liver and epithelium. In the present research, the effect of lead (Pb2+) on Ca2+ -dependent action potential and currents was studied in F77 neuronal soma membrane of Helix aspersa. For this purpose, action pot...

Introduction: Human embryonic stem cells (hESCs) are pluripotent cells that can proliferate and differentiate to many cell types. Their electrophysiological properties have not yet been chracterzed. In this study, the passive properties (such as resting membrane potential, input resistance and capacitance) and the contribution of delayed rectifier K+ channel currents to the membrane conducta...