Na+/H+-exchange in A6 cells: Polarity and vasopressin regulation
| العنوان: | Na+/H+-exchange in A6 cells: Polarity and vasopressin regulation |
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| المؤلفون: | Stephan J. Reshkin, Corinna Helmle-Kolb, Valeria Casavola, Lorenzo Guerra, Heini Murer |
| المصدر: | The Journal of Membrane Biology. 130 |
| بيانات النشر: | Springer Science and Business Media LLC, 1992. |
| سنة النشر: | 1992 |
| مصطلحات موضوعية: | Vasopressin, medicine.medical_specialty, Sodium-Hydrogen Exchangers, Arginine, Physiology, Intracellular pH, Biophysics, Inositol 1,4,5-Trisphosphate, Amiloride, Amphibians, Internal medicine, Cyclic AMP, medicine, Animals, Drug Interactions, Na+/K+-ATPase, Protein kinase A, Cells, Cultured, Protein Kinase C, Protein kinase C, Ion transporter, Epithelial polarity, Dose-Response Relationship, Drug, Chemistry, Sodium, Nephrons, Cell Biology, Hydrogen-Ion Concentration, Arginine Vasopressin, Enzyme Activation, Endocrinology, Carrier Proteins, Anti-Arrhythmia Agents, Protein Kinases |
| الوصف: | We have analyzed the mechanism of Na(+)-dependent pHi recovery from an acid load in A6 cells (an amphibian distal nephron cell line) by using the intracellular pH indicator 2'7'-bis(2-carboxyethyl)5,6 carboxyfluorescein (BCECF) and single cell microspectrofluorometry. A6 cells were found to express Na+/H(+)-exchange activity only on the basolateral membrane: Na+/H(+)-exchange activity follows simple saturation kinetics with an apparent Km for Na+ of approximately 11 mM; it is inhibited in a competitive manner by ethylisopropylamiloride (EIPA). This Na+/H(+)-exchange activity is inhibited by pharmacological activation of protein kinase A (PKA) as well as of protein kinase C (PKC). Addition of arginine vasopressin (AVP) either at low (subnanomolar) or at high (micromolar) concentrations inhibits Na+/H(+)-exchange activity; AVP stimulates IP3 production at low concentrations, whereas much higher concentrations are required to stimulate cAMP formation. These findings suggest that in A6 cells (i) Na+/H(+)-exchange is located in the basolateral membrane and (ii) PKC activation (heralded by IP3 turnover) is likely to be the mediator of AVP action at low AVP concentrations. |
| تدمد: | 1432-1424 0022-2631 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d2f602ccf24cec0efadc36f77d431483Test https://doi.org/10.1007/bf00231889Test |
| حقوق: | CLOSED |
| رقم الانضمام: | edsair.doi.dedup.....d2f602ccf24cec0efadc36f77d431483 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 14321424 00222631 |
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