Al 3 + induced membrane potential changes in Nitellopsis obtusa cells
نویسنده
چکیده
To study the mechanism of aluminium toxicity in plant cells, the effects of aluminium on the electrogenesis of plasma membrane were investigated. We analyzed Al3+ induced membrane potential (Em) changes and potential changes during generation of the action potential (AP) in the internodal cells of Nitellopsis obtusa. Al3+ modified Em decrease significantly. Al3+ didn’t attenuate the amplitude of the action potential too much, though the peak value of the action potential increased. The shift of the second stage of AP repolarization was about 32 mV in positive direction as a result of Al3+ treatment. Al3+ has been suggested to affect Ca2+ homeostasis and H+-ATPase activity.
منابع مشابه
The effect of aluminium on bioelectrical activity of the <Emphasis Type="Italic">Nitellopsis obtusa</Emphasis> cell membrane after H<Superscript>+</Superscript>-ATPase inhibition
Aluminium induced membrane potential (Em) changes and potential changes during repolarization phase of the action potential (AP) in the internodal cells ofNitellopsis obtusa after blocking H-ATPase activity by DCCD were investigated. Micromolar concentrations of DCCD are sufficient to give complete and irreversible inhibition of proton pumping. The membrane potential was measured by conventiona...
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