Guibert, Bertram and Dermietzel, Rolf and Siemen, Detlef (1998) Large conductance channel in plasma membranes of astrocytic cells is functionally related to mitochondrial VDAC-channels. INTERNATIONAL JOURNAL OF BIOCHEMISTRY & CELL BIOLOGY, 30 (3). pp. 379-391. ISSN 1357-2725, 1878-5875
Full text not available from this repository.Abstract
Large conductance anion channels with similar electrophysiological characteristics were found in plasma membranes and in outer mitochondrial membranes of various cell types. Although their large conductance and their peculiar voltage dependence point to a close relation, it was questioned whether they belong to the same family. We therefore compared some biochemical features of a plasmalemmal channel with those known from the mitochondrial channel. Current events were recorded from excised patches of plasma membranes of a rat astrocytic cell line (RGCN). The underlying channels exhibited a conductance of 401 +/- 50 pS. Open probability was highest between +/- 10 mV and gradually approached zero beyond +/- 25 mV Activity as induced by voltage ramps between +/- 40 mV appeared after a delay of up to several min. The delay could be reduced by bathing either side of the patch in an acidic Ringer solution (pH 6.2). 1 mM Al3+ increased the open time at potentials more positive than 20 mV. 10 mM dextran sulfate (MW 8000) caused reversible flickering, increasing the closed probability. 4,4'-diisothiocyanatostilbene-2,2' disulfonic acid (DIDS) also caused a reversible flickering into the dosed state, reducing the apparent single channel amplitude by up to 70% at 0.5 mM DIDS. Application of 5 mM ATP resulted in reversible blockade; ATP was more effective from the outside than from the inside (blocking activity 65% vs. 16% of the patches). We conclude that the large conductance anion channel from astrocytic cells displays electrophysiological and pharmacological characteristics that resemble those of VDAC (Voltage Dependent Anion Channel) from the outer mitochondrial membrane. (C) 1998 Elsevier Science Ltd. All rights reserved.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | DEPENDENT ANION CHANNEL; AMPHIBIAN SKELETAL-MUSCLE; ACTIVE MAMMALIAN PORIN; LARGE UNIT CONDUCTANCE; HUMAN LYMPHOCYTES-T; HUMAN B-LYMPHOCYTES; OUTER-MEMBRANE; VOLTAGE-DEPENDENCE; CHLORIDE CHANNEL; CL CHANNELS; maxi-Cl channel; astrocyte; ATP; aluminum; VDAC |
| Subjects: | 500 Science > 570 Life sciences 600 Technology > 610 Medical sciences Medicine |
| Divisions: | Biology, Preclinical Medicine > Institut für Anatomie |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 28 Feb 2023 07:38 |
| Last Modified: | 28 Feb 2023 07:38 |
| URI: | https://pred.uni-regensburg.de/id/eprint/50049 |
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