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. 1971 Nov;218(3):599–608. doi: 10.1113/jphysiol.1971.sp009635

The independence of electrogenic sodium transport and membrane potential in a molluscan neurone

Michael F Marmor
PMCID: PMC1331603  PMID: 5133950

Abstract

1. The current—voltage relations of the Anisodoris giant neurone (G cell) were studied in the presence and absence of Na pump activity.

2. Inhibition of the electrogenic Na pump with ouabain had no effect on either the presence at warm temperatures (10-15° C), or absence at cold temperatures (0-5° C), of inward-going rectification.

3. Abolition of inward-going rectification in the warm, by replacement of external K with Rb, did not affect the electrogenic Na pump.

4. The current generated by the electrogenic pump was essentially constant between the membrane potentials of — 30 and — 100 mV.

5. The potential produced by the electrogenic pump can be predicted by a modification of the constant field equation.

6. It is estimated that the energy required to extrude Na was between 3160 and 3700 cal/g-atom, and that uncoupled Na efflux during pump activity was typically between 0·2 and 4·0 p-mole/cm2.sec.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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