Summary
In the doubly perfused toad kidney, lanthanum ions were included in the perfusion fluid in a soluble form and were subsequently precipitated as anthanum sulfate. The precipitate was localized by electronmicroscopy.
Precipitate was mainly observed at the tight junctions and in the intercellular spaces. Practically no lanthanum was observed within the cells.
This work locates the paracellular pathway for ion flow proposed from electrophysiological studies (refs. [1–3, 16]) at the level of the tight junctions and of the intercellular spaces.
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Whittembury, G., Rawlins, F.A. Evidence of a paracellular pathway for ion flow in the kidney proximal tubule: Electromicroscopic demonstration of lanthanum precipitate in the tight junction. Pflugers Arch. 330, 302–309 (1971). https://doi.org/10.1007/BF00588582
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DOI: https://doi.org/10.1007/BF00588582