Voltage Regulation
Mostrando 37-48 de 352 artigos, teses e dissertações.
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37. Voltage-dependent and Ca2(+)-activated ion channels in human neutrophils.
To investigate the regulation of membrane voltage and transmembrane ion fluxes in human neutrophils, we studied plasma membrane currents using the whole-cell patch-clamp method. We observed three distinct ion channel currents: (a) a voltage-dependent K+ current, (b) a Ca2(+)-activated K+ current, and (c) a Ca2(+)-activated Cl- current. The voltage-dependent
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38. ATP-Dependent Regulation of an Anion Channel at the Plasma Membrane of Protoplasts from Epidermal Cells of Arabidopsis Hypocotyls.
Although Arabidopsis is the object of many genetic and molecular biology investigations, relatively few studies deal with regulation of its transmembrane ion exchanges. To clarify the role of ion transport in plant development, organ-and tissue-specific ion channels must be studied. We identified a voltage-dependent anion channel in epidermal cells of Arabid
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39. Thyroid Hormone (T3)-Induced Up-Regulation of Voltage-Activated Sodium Current in Cultured Postnatal Hippocampal Neurons Requires Secretion of Soluble Factors from Glial Cells
We have previously shown that treatment with the thyroid hormone T3 increases the voltage-gated Na+current density (Nav-D) in hippocampal neurons from postnatal rats, leading to accelerated action potential upstrokes and increased firing frequencies. Here we show that the Na+ current regulation depends on the presence of glial cells, which secrete a heat-ins
The Endocrine Society.
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40. Two types of anion channel currents in guard cells with distinct voltage regulation.
Transpirational water loss by plants is reduced by closing of stomatal pores in the leaf epidermis. Anion channels in the plasma membrane of guard cells may provide a key molecular mechanism for control of stomatal closing in leaves. However, central questions regarding the regulation, diversity, and function of anion channels in guard cells and other higher
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41. Ca2+ and nucleotide dependent regulation of voltage dependent anion channels in the plasma membrane of guard cells.
Using the patch-clamp technique we discovered that the voltage dependent anion channels in the plasma membrane of guard cells are activated by a rise in cytoplasmic Ca2+ in the presence of nucleotides. Upon activation, these anion channels catalyse anion currents 10-20 times higher than in the inactivated state, thus shifting the plasma membrane from a K+ co
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42. The Pore of Plant K+ Channels Is Involved in Voltage and pH Sensing: Domain-Swapping between Different K+ Channel α-Subunits
Plant K+ uptake channel types differ with respect to their voltage, Ca2+, and pH dependence. Here, we constructed recombinant chimeric channels between KST1, a member of the inward-rectifying, acid-activated KAT1 family, and AKT3, a member of the weakly voltage-dependent, proton-blocked AKT2/3 family. The homologous pore regions of AKT3 (amino acids 216 to 2
American Society of Plant Physiologists.
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43. T-type calcium channels are regulated by hypoxia/reoxygenation in ventricular myocytes
Low-voltage-activated calcium channels are reexpressed in ventricular myocytes in pathological conditions associated with hypoxic episodes, but a direct relation between oxidative stress and T-type channel function and regulation in cardiomyocytes has not been established. We aimed to investigate low-voltage-activated channel regulation under oxidative stres
American Physiological Society.
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44. Dendritic Calcium Channels and Their Activation by Synaptic Signals in Auditory Coincidence Detector Neurons
The avian nucleus laminaris (NL) encodes the azimuthal location of low-frequency sound sources by detecting the coincidence of binaural signals. Accurate coincidence detection requires precise developmental regulation of the lengths of the fine, bitufted dendrites that characterize neurons in NL. Such regulation has been suggested to be driven by local, syna
American Physiological Society.
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45. Voltage-gated calcium channel currents in human coronary myocytes. Regulation by cyclic GMP and nitric oxide.
Voltage-gated Ca2+ channels contribute to the maintenance of contractile tone in vascular myocytes and are potential targets for vasodilating agents. There is no information available about their nature and regulation in human coronary arteries. We used the whole-cell voltage-clamp technique to characterize Ca2+-channel currents immediately after enzymatic d
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46. Large conductance Ca(2+)-activated K+ channels are involved in both spike shaping and firing regulation in Helix neurones.
1. The role of BK-type calcium-dependent K+ channels (K+Ca) in cell firing regulation was evaluated by performing whole-cell voltage clamp and patch clamp experiments on the U cell neurones in the snail Helix pomatia. These cells were selected because most of the repolarizing K+ current flowed through K+Ca channels. 2. U cells generated overshooting Ca(2+)-d
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47. Reconstituted voltage-sensitive sodium channel from Electrophorus electricus: chemical modifications that alter regulation of ion permeability.
At equilibrium, voltage-sensitive sodium channels normally are closed at all potentials. They open transiently in response to changes in membrane voltage or chronically under the influence of certain neurotoxins. Covalent modifications that result in chronic opening may help identify molecular domains involved in conductance regulation. Here, the purified so
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48. Sequence and functional expression in Xenopus oocytes of a human insulinoma and islet potassium channel.
Regulation of insulin secretion involves the coordinated control of ion channels in the beta-cell membrane. We have isolated and characterized cDNA and genomic clones encoding a voltage-dependent K+ channel isoform expressed in human islets and in a human insulinoma. This K+ channel isoform, designated hPCN1, with a deduced amino acid sequence of 613 residue