Dual modulation of swelling‐activated chloride current by NO and NO donors in rabbit portal vein myocytes
| Autor: | W. A. Large, Iain A. Greenwood, D. C. Ellershaw |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
medicine.medical_specialty
Patch-Clamp Techniques Physiology In Vitro Techniques S-Nitroso-N-Acetylpenicillamine Nitric Oxide Chloride Muscle Smooth Vascular Membrane Potentials chemistry.chemical_compound Meglumine Chloride Channels Internal medicine Cyclic GMP-Dependent Protein Kinases medicine Animals Myocyte Nitric Oxide Donors Patch clamp Protein kinase A Cyclic GMP Cells Cultured Cell Size Chelating Agents Portal Vein Penicillamine Sodium Snap Original Articles EGTA Endocrinology chemistry Guanylate Cyclase Biophysics Phosphorylation Endothelium Vascular Rabbits Swelling medicine.symptom Perspectives Signal Transduction medicine.drug |
| Zdroj: | The Journal of Physiology. 528:15-24 |
| ISSN: | 1469-7793 0022-3751 |
| DOI: | 10.1111/j.1469-7793.2000.00015.x |
| Popis: | 1. The effects of authentic NO and the NO donor S-nitroso-N-acetylpenicillamine (SNAP) on swelling-activated chloride currents (Iswell) were investigated in freshly dispersed rabbit portal vein smooth muscle cells. Iswell was recorded with the perforated patch configuration of the whole-cell patch clamp technique. 2. In approximately 50 % of cells NO and SNAP inhibited the amplitude of Iswell by about 45 % in a voltage-independent manner. Iswell was also inhibited by an inhibitor of NO-sensitive guanylate cyclase (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) and by KT5823, an inhibitor of cGMP-dependent protein kinase. 3. In other cells both NO and SNAP enhanced Iswell by about 40 % in a voltage-independent manner. A similar increase was produced by application of the cell-permeable cGMP analogue 8-bromo-guanosine 3', 5'-cyclic monophosphate (8-Br-cGMP). However, 8-Br-cGMP had no effect on current amplitude in cells pre-treated with KT5823. In contrast 8-Br-cGMP increased the amplitude of Iswell in cells which had been pre-treated with ODQ. 4. SNAP also modulated Iswell recorded in the conventional whole-cell configuration with internal solutions containing 10 mM EGTA to rule out any contribution from Ca2+-activated Cl- currents. 5. These data suggest that the amplitude of Iswell can be enhanced by NO via a cGMP-dependent phosphorylation and inhibited by NO in a cGMP-independent manner. |
| Databáze: | OpenAIRE |
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