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. 1967 May 1;50(5):1353–1375. doi: 10.1085/jgp.50.5.1353

NMR Evidence for Complexing of Na+ in Muscle, Kidney, and Brain, and by Actomyosin. The Relation of Cellular Complexing of Na+ to Water Structure and to Transport Kinetics

Freeman W Cope 1
PMCID: PMC2225705  PMID: 6033590

Abstract

The nuclear magnetic resonance (NMR) spectrum of Na+ is suitable for qualitative and quantitative analysis of Na+ in tissues. The width of the NMR spectrum is dependent upon the environment surrounding the individual Na+ ion. NMR spectra of fresh muscle compared with spectra of the same samples after ashing show that approximately 70% of total muscle Na+ gives no detectable NMR spectrum. This is probably due to complexation of Na+ with macromolecules, which causes the NMR spectrum to be broadened beyond detection. A similar effect has been observed when Na+ interacts with ion exchange resin. NMR also indicates that about 60% of Na+ of kidney and brain is complexed. Destruction of cell structure of muscle by homogenization little alters the per cent complexing of Na+. NMR studies show that Na+ is complexed by actomyosin, which may be the molecular site of complexation of some Na+ in muscle. The same studies indicate that the solubility of Na+ in the interstitial water of actomyosin gel is markedly reduced compared with its solubility in liquid water, which suggests that the water in the gel is organized into an icelike state by the nearby actomyosin molecules. If a major fraction of intracellular Na+ exists in a complexed state, then major revisions in most theoretical treatments of equilibria, diffusion, and transport of cellular Na+ become appropriate.

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Selected References

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  1. Baker H. P., Saroff H. A. Binding of sodium ions to beta-lactoglobulin. Biochemistry. 1965 Aug;4(8):1670–1677. doi: 10.1021/bi00884a033. [DOI] [PubMed] [Google Scholar]
  2. CARR C. W. Studies on the binding of small ions in protein solutions with the use of membrane electrodes. VI. The binding of sodium and potassium ions in solutions of various proteins. Arch Biochem Biophys. 1956 Jun;62(2):476–484. doi: 10.1016/0003-9861(56)90146-1. [DOI] [PubMed] [Google Scholar]
  3. COPE F. W. A THEORY OF ION TRANSPORT ACROSS CELL SURFACES BY A PROCESS ANALOGOUS TO ELECTRON TRANSPORT ACROSS LIQUID-SOLID INTERFACES. Bull Math Biophys. 1965 Mar;27:99–109. doi: 10.1007/BF02476472. [DOI] [PubMed] [Google Scholar]
  4. Cope F. W. Nuclear magnetic resonance evidence for complexing of sodium ions in muscle. Proc Natl Acad Sci U S A. 1965 Jul;54(1):225–227. doi: 10.1073/pnas.54.1.225. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. HINKE J. A. Glass micro-electrodes for measuring intracellular activities of sodium and potassium. Nature. 1959 Oct 17;184(Suppl 16):1257–1258. doi: 10.1038/1841257a0. [DOI] [PubMed] [Google Scholar]
  6. Ho C., Waugh D. F. Interactions of bovine alpha-s-casein with small ions. J Am Chem Soc. 1965 Jan 5;87(1):110–117. doi: 10.1021/ja01079a020. [DOI] [PubMed] [Google Scholar]
  7. JARDETZKY O., WERTZ J. E. The complexing of sodium ion with some common metabolites. Arch Biochem Biophys. 1956 Dec;65(2):569–572. doi: 10.1016/0003-9861(56)90215-6. [DOI] [PubMed] [Google Scholar]
  8. LEV A. A. OPREDELENIE AKTIVNOSTI I KO'EFFITSIENTOV AKTIVNOSTI IONOV KALIIA I NATRIIA V MYSHECHNYKH VOLOKNAKH LIAGUSHKI PRI POMOSHCHI KATIONCHUVSTVITEL'NYKH STEKLIANNYKH MIKRO'ELEKTRODOV. Biofizika. 1964;9:686–694. [PubMed] [Google Scholar]
  9. LING G. N. PHYSIOLOGY AND ANATOMY OF THE CELL MEMBRANE: THE PHYSICAL STATE OF WATER IN THE LIVING CELL. Fed Proc. 1965 Mar-Apr;24:S103–S112. [PubMed] [Google Scholar]
  10. LING G. Muscle electrolytes. Am J Phys Med. 1955 Feb;34(1):89–101. [PubMed] [Google Scholar]
  11. Ling G. N., Ochsenfeld M. M. Studies on ion accumulation in muscle cells. J Gen Physiol. 1966 Mar;49(4):819–843. doi: 10.1085/jgp.49.4.819. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Ling G. N., Ochsenfeld M. M. Studies on the ionic permeability of muscle cells and their models. Biophys J. 1965 Nov;5(6):777–807. doi: 10.1016/S0006-3495(65)86752-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Ling G. N. The membrane theory and other views for solute permeability, distribution, and transport in living cells. Perspect Biol Med. 1965 Autumn;9(1):87–106. doi: 10.1353/pbm.1965.0029. [DOI] [PubMed] [Google Scholar]
  14. Ling G. N. The physical state of water in living cell and model systems. Ann N Y Acad Sci. 1965 Oct 13;125(2):401–417. doi: 10.1111/j.1749-6632.1965.tb45406.x. [DOI] [PubMed] [Google Scholar]
  15. SAROFF H. A. The binding of ions to the muscle proteins; a theory for K+ and Na+ binding based on a hydrogen-bonded and chelated model. Arch Biochem Biophys. 1957 Sep;71(1):194–203. doi: 10.1016/0003-9861(57)90021-8. [DOI] [PubMed] [Google Scholar]
  16. SHAW F. H., SIMON S. E. The nature of the sodium and potassium balance in nerve and muscle cells. Aust J Exp Biol Med Sci. 1955 Apr;33(2):153–177. doi: 10.1038/icb.1955.17. [DOI] [PubMed] [Google Scholar]
  17. SIMON S. E. Ionic partition and fine structure in muscle. Nature. 1959 Dec 26;184:1978–1982. doi: 10.1038/1841978a0. [DOI] [PubMed] [Google Scholar]
  18. SIMON S. E., SHAW F. H., BENNETT S., MULLER M. The relationship between sodium, potassium, and chloride in amphibian muscle. J Gen Physiol. 1957 May 20;40(5):753–777. doi: 10.1085/jgp.40.5.753. [DOI] [PMC free article] [PubMed] [Google Scholar]

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