Further Observations on Asymmetrical Solute Movement across Membranes

J Gen Physiol. 1968 January 1; 51(1): 1–12.

PMCID: PMC2201158

T. J. Franz, William R. Galey, and J. T. Van Bruggen

From the Department of Biochemistry, University of Oregon Medical School, Portland, Oregon 97201.

Captain Franz's present address is General Delivery, Letterman General Hospital, San Francisco, California 94129. Address communications regarding this work to J. T. Van Bruggen, Department of Biochemistry, University of Oregon Medical School, Portland, Oregon 97201

Received June 2, 1967.

This article has been cited by other articles in PMC.

Abstract

The permeability of frog skin under the influence of urea hyperosmolarity has been studied. Flux ratio asymmetry has been demonstrated again for tracer mannitol. The inhibitors DNP, CN^-, and ouabain have been used to eliminate active sodium transport and it was found that urea hyperosmolarity produces asymmetrical mannitol fluxes on frog skins having no short-circuit current. These findings suggest that flux ratio asymmetry is due to solute interaction and is unrelated to sodium transport. Studies with a synthetic membrane show clearly that bulk flow of fluid can produce a "solvent drag" effect and change flux ratios. When bulk flow is blocked and solute gradients allowed their full expression, then solute interaction "solute drag" is easily demonstrable in a synthetic system.

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Selected References

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

Ussing, HH. Anomalous transport of electrolytes and sucrose through the isolated frog skin induced by hypertonicity of the outside bathing solution. Ann N Y Acad Sci. 1966 Jul 14;137(2):543–555. [PubMed]
Franz, TJ; Van Bruggen, JT. A possible mechanism of action of DMSO. Ann N Y Acad Sci. 1967 Mar 15;141(1):302–309. [PubMed]
Franz, TJ; Van Bruggen, JT. Hyperosmolarity and the net transport of nonelectrolytes in frog skin. J Gen Physiol. 1967 Mar;50(4):933–949. [PubMed]
Schultz, SG; Fuisz, RE; Curran, PF. Amino acid and sugar transport in rabbit ileum. J Gen Physiol. 1966 May;49(5):849–866. [PubMed]
ANDERSEN, B; USSING, HH. Solvent drag on non-electrolytes during osmotic flow through isolated toad skin and its response to antidiuretic hormone. Acta Physiol Scand. 1957 Jun 8;39(2-3):228–239. [PubMed]