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A R Akopian

Publications and source records attributed to A R Akopian.

5 recordsLinked to original sources
PubMed1979

[Relationship between the magnitude of the inflowing current of isolated Limnea stagnalis mollusk neurons and the external concentration of the current-bearing calcium and strontium ions].

The dose-inward current relationships for current-carrying ions Ca2+ and Sr2+ were studied by means of intracellular dialysis and voltage clamp in isolated neurons of the mollusc Limnea stagnalis. For Ca2+ and Sr2+ ions these relationships had ceiling. The data obtained are explained in terms of activation theory using two-barrier model of calcium channel. Values of velocity constants vx for ion x2+ transition over the second energetic barrier and of constants Kx corresponding to effectiveness of binding in the channel's entrance were determined: vca:vsr = 1:2; KCa = 1400 M-1; KSr = 270 M-1.

Animals↗
PubMedDate not supplied

[Dopamine modification of the Ca-component of the action potential in the neuron soma of the mollusk L. stagnalis].

Dopamine has been found to decrease reversibly the action potential rising phase in identified L. stagnalis neurones. Using voltage-clamp and intracellular dialysis techniques it is shown that dopamine inhibits electroexcitable Ca-current, and changes in Ca-current determine those in the action potential shape. Serotonin and adrenaline influence the Ca-current in a similar way as dopamine does. Inhibition of Ca-conductance is found not to be related to possible effect of these neuromediators on intracellular level of free Ca ions or cyclic AMP.

Action Potentials↗