Calcium Content and Net Fluxes in Squid Giant Axons

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Axons freshly dissected from living specimens of the tropical squid Dorytheutis plei have a calcium content of 68 tzmol/kg of axoplasm. Fibers stimulated at 100 impuises/s in 100 mM Ca seawater increase their Ca content by 150/zmol/ kg.min; axons placed in 3 Ca (choline) seawater increase their Ca content by 12 /zmol/kg.min. Axons loaded with 0.2-1.5 mmol Ca/kg of axoplasm extruded Ca with a half time of 15-30 min when allowed to recover in 3 Ca (Na) seawater. The half time for recovery of loaded axons poisoned with carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP) and iodoacetic acid (IAA) is about the same as control axons. Axons placed in 40 mM Na choline seawater (to reduce chemical gradient for Na) or in 40 mM Na, 410 mM K seawater to reduce the electrochemical gradient for Na to near zero either fail to lose previously loaded Ca or gain further

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Calcium Content and Net Fluxes in Squid Giant Axons

Axons freshly dissected from living specimens of the tropical squid Dorytheutis plei have a calcium content of 68 tzmol/kg of axoplasm. Fibers stimulated at 100 impuises/s in 100 mM Ca seawater increase their Ca content by 150/zmol/ kg.min; axons placed in 3 Ca (choline) seawater increase their Ca content by 12 /zmol/kg.min. Axons loaded with 0.2-1.5 mmol Ca/kg of axoplasm extruded Ca with a ha...

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Calcium content and net fluxes in squid giant axons

Axons freshly dissected from living specimens of the tropical squid Dorytheutis plei have a calcium content of 68 mumol/kg of axoplasm. Fibers stimulated at 100 impulses/s in 100 mM Ca seawater increase their Ca content by 150 mumol/kg.min; axons placed in 3 Ca (choline) seawater increase their Ca content by 12 mumol/kg.min. Axons loaded with 0.2--1.5 mmol Ca/kg of axoplasm extruded Ca with a h...

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Tracer and Nontracer Potassium Fluxes in Squid Giant Axons and the Effects of Changes in External Potassium Concentration and Membrane Potential

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Removal of Potassium Negative Resistance in Perfused Squid Giant Axons

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تاریخ انتشار 2003