The two-microelectrode technique of voltage clamping sheep cardiac Purkinje fibers was used to examine the changes in contraction which occur during trains of voltage clamps. (A "train" is defined as a series of voltage clamps delivered at a particular rate, beginning after a rest long enough that the effects of previous stimulation have died away.) Contractions showed striking staircases, or p...

The traditional method of recording ionic currents in neurons has been with voltage-clamp steps. Other waveforms such as action potentials (APs) can be used. The AP clamp method reveals contributions of ionic currents that underlie excitability during an AP (Bean BP. Nat Rev Neurosci 8: 451-465, 2007). A novel usage of the method is described in this report. An experimental recording of an AP f...

PURPOSE The sense of vision in humans is robust, and visual flickering is rarely experienced. To investigate this mechanism, electrophysiological and molecular biological techniques were used on human cone and rod photoreceptors. METHODS Voltage-gated currents were recorded using the patch-clamp technique on isolated human cones, and especially their voltage-gated Na+ currents were analyzed i...

TO THE EDITOR: Cell membrane capacitance Cm is a fundamental property of excitable cells. It scales with the cell surface area and is therefore used for cell size estimation and most important for normalizing currents and conductances. Consequently, proper knowledge of Cm is also crucial for accurate cell modeling (7). Whole cell patch-clamp technique has led to the development of elaborate met...