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. 1983 Apr;337:173–182. doi: 10.1113/jphysiol.1983.sp014618

Insensitivity of activation delays in potassium and sodium channels to heavy water in Myxicola giant axons.

C L Schauf
PMCID: PMC1199101  PMID: 6308235

Abstract

Substitution of heavy water (D2O) for H2O slows the Na+ and K+ currents in Myxicola giant axons by 40-50% at 5 degrees C. In contrast, the delays in Na+ K+ activation which can be produced by hyperpolarizing pre-pulses are not affected by solvent substitution. We suggest that in the cascade of transitions leading to the opening of Na+ and K+ channels, D2O affects only the final step that establishes the aqueous pore across the membrane.

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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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