Use of Ion-Channel Modulating Agents to Study Cyanobacterial Na(+) - K(+) Fluxes
Overview
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Here we describe an experimental design aimed to investigate changes in total cellular levels of Na(+) and K(+) ions in cultures of freshwater filamentous cyanobacteria. Ion concentrations were measured in whole cells by flame photometry. Cellular Na(+) levels increased exponentially with rising alkalinity, with K(+) levels being maximal for optimal growth pH (~8). At standardized pH conditions, the increase in cellular Na(+), as induced by NaCl at 10 mM, was coupled by the two sodium channel-modulating agents lidocaine hydrochloride at 1 microM and veratridine at 100 microM. Both the channel-blockers amiloride (1 mM) and saxitoxin (1 microM), decreased cell-bound Na(+) and K(+) levels. Results presented demonstrate the robustness of well-defined channel blockers and channel-activators in the study of cyanobacterial Na(+)- K(+) fluxes.
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PMID: 24956074 PMC: 4073136. DOI: 10.3390/toxins6061896.
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