Learn More
1. The inward facing membranes of in vitro frog skin epithelium were depolarized with solutions of high K concentration. The electrical properties of the epithelium are then expected to be governed by the outward facing, Na-selective membrane.2. In this state, the transepithelial voltage (V) was clamped to zero and step-changes of Na activity in the outer(More)
The voltage dependecies of Na and Cl fluxes were investigated in the isolated toad skin. With Cl-Ringer's on both sides Cl outflux varied very little with clamping voltage. The same was true for the influx of Cl at depolarizing voltages (psii -psio lessthan0 mV), wheras hyperpolarization led to a marked increase in this flux. A net chloride influx under(More)
The isolated epithelium of toad skin was disintegrated into single cells by treatment with collagenase and trypsine. Chloride channels of cell-attached and excised inside-out apical membrane-patches of mitochondria-rich cells were studied by the patch-clamp technique. The major population of Cl- channels constituted small 7-pS linear channels in symmetrical(More)
A computer model of ion transport across amphibian skin epithelium containing two types of cellular units, their relative number and sizes, and a paracellular pathway has been developed. The two cellular units are, (1) a large Na+ transporting compartment representing the major epithelium from stratum granulosum to str. germinativum, and (2) a small, Cl−(More)
1. Mitochondria-rich (MR) cells in free suspension were obtained by collagenase and trypsin treatments of toad skin epithelium and studied by whole-cell voltage clamp and membrane current fluctuation analysis. 2. Cells studied with a 100 microM amiloride and 5 mM Ba2+ Ringer solution on the outside and 10 mM Cs+ in the pipette generated large membrane(More)
The Sf9 insect Spodoptora frugiperda cell line was used for heterologous expression of the cloned human cystic fibrosis transmembrane conductance regulator (CFTR) cDNA, or the cloned β-galactosidase gene, using the baculovirus Autographa califonica as the infection vector. Using application of the patch-clamp technique, evidence for functional expression of(More)
1. Active Cl- currents were studied in short-circuited toad skin epithelium in which the passive voltage-activated Cl- current is zero. Under visual control double-barrelled microelectrodes were used for impaling principal cells from the serosal side, or for measuring the pH profile in the solution bathing the apical border. 2. The net inward (active) 36Cl-(More)
1. The control by intracellular cyclic AMP and beta-adrenergic stimulation of chloride conductance was studied in toad skin epithelium mounted in a chamber on the stage of an upright microscope. Impalement of identified principal cells from the serosal side with single-barrelled conventional or double-barrelled Cl(-)-sensitive microelectrodes was performed(More)