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. 1974 Aug;240(3):535–566. doi: 10.1113/jphysiol.1974.sp010622

Active transport of iodide and other anions across the choroid plexus

Ernest M Wright
PMCID: PMC1330994  PMID: 4369751

Abstract

1. An in vitro preparation of the frog choroid plexus was used to study mechanisms of anion transport.

2. It was observed that, in the absence of electrochemical potential gradients, there were net fluxes of I-, SCN-, TcO4-, and Br- across the plexus, from the ventricular to the serosal surface. The net flux of I- reached a maximum at a concentration of 250 μM.

3. On the basis of competition effects it was concluded that the affinity of the transport process for anions was: ClO4 > ReO4 ∼ BF4 > SCN ∼ SeCN > I > NO3 > Br > Cl.

4. Ouabain, oligomycin, phloretin and 2,4-DNP inhibited the net transport of anions, but phlorrhizin, furosemide, 2,4,6-trinitro-m-cresolate, reducing agents, and antithyroid agents did not. Ouabain and phloretin were only effective on the ventricular side of the preparation.

5. Anion transport required the presence of both Na and K. The requirement for Na was specific, but Rb, and to a lesser extent Cs, could substitute for K. Na in either the ventricular or the serosal fluids could partially stimulate anion transport, but K was only effective in the ventricular solution.

6. TcO4-, SCN- and I- were accumulated within the choroidal epithelium from the ventricular fluid, but not from the serosal fluid. Accumulation was inhibited by ouabain and ClO4-.

7. The unidirectional influx of I- across the apical cell membrane was about an order of magnitude greater than the flux across the epithelium. This flux was inhibited by ClO4-, ouabain, and Na-free solutions.

8. These experiments suggest the following mechanism for anion transport across the plexus: anions are actively transported into the epithelium, by a ouabain sensitive, Na/K dependent pump located in the brush border membrane. The anions are accumulated within the epithelium, and, finally, they pass into the serosal fluid down their electrochemical potential gradient. Relations between anion transport, Na/K transport, and Na/K ATPases are discussed.

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Selected References

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

  1. BECKER B. Cerebrospinal fluid iodide. Am J Physiol. 1961 Dec;201:1149–1151. doi: 10.1152/ajplegacy.1961.201.6.1149. [DOI] [PubMed] [Google Scholar]
  2. CURRAN P. F., HERRERA F. C., FLANIGAN W. J. The effect of Ca and antidiuretic hormone on Na transport across frog skin. II. Sites and mechanisms of action. J Gen Physiol. 1963 May;46:1011–1027. doi: 10.1085/jgp.46.5.1011. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Coben L. A. Uptake of iodide by choroid plexus in vivo and location of the iodide pump. Am J Physiol. 1969 Jul;217(1):89–97. doi: 10.1152/ajplegacy.1969.217.1.89. [DOI] [PubMed] [Google Scholar]
  4. DIAMOND J. M. The mechanism of solute transport by the gall-bladder. J Physiol. 1962 May;161:474–502. doi: 10.1113/jphysiol.1962.sp006899. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Diamond J. M. A rapid method for determining voltage-concentration relations across membranes. J Physiol. 1966 Mar;183(1):83–100. doi: 10.1113/jphysiol.1966.sp007852. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Diamond J. M., Wright E. M. Biological membranes: the physical basis of ion and nonelectrolyte selectivity. Annu Rev Physiol. 1969;31:581–646. doi: 10.1146/annurev.ph.31.030169.003053. [DOI] [PubMed] [Google Scholar]
  7. Glynn I. M. Membrane adenosine triphosphatase and cation transport. Br Med Bull. 1968 May;24(2):165–169. doi: 10.1093/oxfordjournals.bmb.a070620. [DOI] [PubMed] [Google Scholar]
  8. Gunn R. B., Dalmark M., Tosteson D. C., Wieth J. O. Characteristics of chloride transport in human red blood cells. J Gen Physiol. 1973 Feb;61(2):185–206. doi: 10.1085/jgp.61.2.185. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Gunn R. B., Tosteson D. C. The effect of 2,4,6-trinitro-m-cresol on cation and anion transport in sheep red blood cells. J Gen Physiol. 1971 May;57(5):593–609. doi: 10.1085/jgp.57.5.593. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. HOSHIKO T., USSING H. H. The kinetics of Na24 flux across amphibian skin and bladder. Acta Physiol Scand. 1960 May 25;49:74–81. doi: 10.1111/j.1748-1716.1960.tb01931.x. [DOI] [PubMed] [Google Scholar]
  11. Hagiwara S., Toyama K., Hayashi H. Mechanisms of anion and cation permeations in the resting membrane of a barnacle muscle fiber. J Gen Physiol. 1971 Apr;57(4):408–434. doi: 10.1085/jgp.57.4.408. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Kaback H. R. Transport across isolated bacterial cytoplasmic membranes. Biochim Biophys Acta. 1972 Aug 4;265(3):367–416. doi: 10.1016/0304-4157(72)90014-7. [DOI] [PubMed] [Google Scholar]
  13. Kimmich G. A. Active sugar accumulation by isolated intestinal epithelial cells. A new model for sodium-dependent metabolite transport. Biochemistry. 1970 Sep 15;9(19):3669–3677. doi: 10.1021/bi00821a004. [DOI] [PubMed] [Google Scholar]
  14. Kimmich G. A., Randles J. Effect of K+ and K+ gradients on accumulation of sugars by isolated intestinal epithelial cells. J Membr Biol. 1973;12(1):23–46. doi: 10.1007/BF01869990. [DOI] [PubMed] [Google Scholar]
  15. Machen T. E., Diamond J. M. The mechanism of anion permeation in thorium-treated gallbladder. J Membr Biol. 1972;8(1):63–96. doi: 10.1007/BF01868095. [DOI] [PubMed] [Google Scholar]
  16. Oldendorf W. H., Sisson W. B., Iisaka Y. Affinity of ventricular 99mTc pertechnetate and iodide ions for choroid plexus. Arch Neurol. 1970 Jul;23(1):74–79. doi: 10.1001/archneur.1970.00480250078011. [DOI] [PubMed] [Google Scholar]
  17. Pollay M., Kaplan R. Transependymal transport of thiocyanate. J Neurobiol. 1972;3(4):339–346. doi: 10.1002/neu.480030407. [DOI] [PubMed] [Google Scholar]
  18. Quinton P. M., Wright E. M., Tormey J. M. Localization of sodium pumps in the choroid plexus epithelium. J Cell Biol. 1973 Sep;58(3):724–730. doi: 10.1083/jcb.58.3.724. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. SCHULTZ S. G., ZALUSKY R. ION TRANSPORT IN ISOLATED RABBIT ILEUM. I. SHORT-CIRCUIT CURRENT AND NA FLUXES. J Gen Physiol. 1964 Jan;47:567–584. doi: 10.1085/jgp.47.3.567. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Schultz S. G., Curran P. F. Coupled transport of sodium and organic solutes. Physiol Rev. 1970 Oct;50(4):637–718. doi: 10.1152/physrev.1970.50.4.637. [DOI] [PubMed] [Google Scholar]
  21. WELCH K. Active transport of iodide by choroid plexus of the rabbit in vitro. Am J Physiol. 1962 Apr;202:757–760. doi: 10.1152/ajplegacy.1962.202.4.757. [DOI] [PubMed] [Google Scholar]
  22. WELCH K. Concentration of thiocyanate by the choroid plexus of the rabbit in vitro. Proc Soc Exp Biol Med. 1962 Apr;109:953–954. doi: 10.3181/00379727-109-27389. [DOI] [PubMed] [Google Scholar]
  23. WOLFF J. TRANSPORT OF IODIDE AND OTHER ANIONS IN THE THYROID GLAND. Physiol Rev. 1964 Jan;44:45–90. doi: 10.1152/physrev.1964.44.1.45. [DOI] [PubMed] [Google Scholar]
  24. Welch K. The secretion of cerebrospinal fluid by lamina epithelialis. Monogr Surg Sci. 1967 Sep;4(3):155–192. [PubMed] [Google Scholar]
  25. Wright E. M. Accumulation and transport of amino acids by the frog choroid plexus. Brain Res. 1972 Sep 15;44(1):207–219. doi: 10.1016/0006-8993(72)90376-9. [DOI] [PubMed] [Google Scholar]
  26. Wright E. M. Active transport of lysergic acid diethylamide. Nature. 1972 Nov 3;240(5375):53–54. doi: 10.1038/240053a0. [DOI] [PubMed] [Google Scholar]
  27. Wright E. M. Mechanisms of ion transport across the choroid plexus. J Physiol. 1972 Oct;226(2):545–571. doi: 10.1113/jphysiol.1972.sp009997. [DOI] [PMC free article] [PubMed] [Google Scholar]

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