An estimate of the salt concentration in the lateral intercellular spaces of rabbit gall-bladder during maximal fluid transport

1969 ◽  
Vol 1 (1) ◽  
pp. 194-213 ◽  
Author(s):  
Terry E. Machen ◽  
Jared M. Diamond
Keyword(s):  
Gall Bladder ◽  
Salt Concentration ◽  
Fluid Transport ◽  
Intercellular Spaces ◽  
Lateral Intercellular Spaces

Tracing Permeation Pathways Across Epithelia

1971 ◽  
Vol 29 ◽  
pp. 394-395
Author(s):  
J. McD. Tormey ◽  
E. M. Wright ◽  
A. P. Smulders
Keyword(s):  
Gall Bladder ◽  
Small Molecules ◽  
Membrane Transport ◽  
Fluid Transport ◽  
Central Problem ◽  
Biological Transport ◽  
Intercellular Spaces ◽  
Bladder Epithelium ◽  
Anatomical Changes ◽  
Lateral Intercellular Spaces

The route by which small molecules, such as water, electrolytes and sugars, cross the membranes of epithelial tissues is a central problem in biological transport. Good methods for quantitatively localizing small diffusible molecules within tissues, or for unambiguously demonstrating membrane transport sites, have yet to be developed. In their absence indirect approaches based on anatomical changes have had to be used.The lateral intercellular spaces of gall bladder epithelium were several years ago found to be widely dilated when salt and water were being actively pumped across the tissue. The spaces were collapsed in the absence of transport. Similar phenomena were subsequently observed in several other tissues. This has been widely interpreted as proof that the spaces are the route of fluid transport.

Effects of amiloride on the endolymphatic sac

1989 ◽  
Vol 103 (5) ◽  
pp. 466-470 ◽  
Author(s):  
M. Takumida ◽  
D. Bagger-Sjöbäck
Keyword(s):  
Epithelial Cells ◽  
Ion Exchange ◽  
Fluid Transport ◽  
Endolymphatic Hydrops ◽  
Endolymphatic Sac ◽  
Intercellular Spaces ◽  
Exchange System ◽  
Fluid Exchange ◽  
Apical Portion ◽  
Lateral Intercellular Spaces

AbstractThe effect of amiloride on the murine endolymphatic sac was investigated. The amiloride caused collapse of the lateral intercellular spaces in the endolymphatic sac epithelium and a subsequent mild endolymphatic hydrops. These changes indicated a decreased absorption of endolymph in the endolymphatic sac. Amiloride is known to inhibit the transcellular fluid transport without inducing any changes in the paracellular fluid transport. It is therefore suggested that amiloride specially inhibits the fluid and ion exchange in the apical portion of the epithelial cells resulting a decrease in transcellular fluid transport across the endolymphatic sac epithelium. The transcellular fluid transport seems to be one of the main mechanisms in the endolymphatic sac fluid exchange system.

The Lateral Intercellular Spaces in the Endolymphatic Sac. A Pathway for Fluid Transport?

1985 ◽  
Vol 100 (sup426) ◽  
pp. 3-17 ◽  
Author(s):  
Ulla Friberg ◽  
Dan Bagger-Sjöbäck ◽  
Helge Rask-Andersen
Keyword(s):  
Fluid Transport ◽  
Endolymphatic Sac ◽  
Intercellular Spaces ◽  
Lateral Intercellular Spaces

scholarly journals Fluid transport and the dimensions of cells and interspaces of living Necturus gallbladder.

1979 ◽  
Vol 73 (3) ◽  
pp. 287-305 ◽  
Author(s):  
K R Spring ◽  
A Hope
Keyword(s):  
Cell Volume ◽  
Fluid Transport ◽  
Control Volume ◽  
Salt Transport ◽  
Intercellular Spaces ◽  
Control Value ◽  
Necturus Gallbladder ◽  
Tissue Resistance ◽  
Lateral Intercellular Spaces ◽  
Small Resistance

The volume of the cells and lateral intercellular spaces were measured in living Necturus gallbladder epithelium. Under control conditions, the volume of the lateral spaces was 9% of the cell volume. Replacement of mucosal NaCl by sucrose or tetramethylammonium chloride (TMACl) caused intercellular spaces to collapse. During mucosal NaCl replacement, cell volume decreased to 79% of its control value. When NaCl was reintroduced into the mucosal bath, the intercellular spaces reopened and the cells returned to control volume. The NaCl active transport rate, calculated from the rate of cell volume decrease, was 266 pM/cm2.s, close to the observed rate of transepithelial salt transport. It was calculated from the decrease in cell volume that all of the intracellular NaCl was transported out of the cell during removal of mucosal NaCl. The flux of salt across the apical membrane, calculated from the rate of cell volume increase upon reintroducing mucosal NaCl, was 209 pM/cm2.s, in good agreement with estimates by other methods. The electrical resistance of the tight junctions was estimated to be 83.9% of the total tissue resistance in control conditions, suggesting that the lateral intercellular spaces normally offer only a small resistance to electrolyte movement.

Video microscopic measurements of diffusion and flow in cultured kidney cells

1992 ◽  
Vol 50 (1) ◽  
pp. 420-421
Author(s):  
Kenneth R. Spring ◽  
Peter M. Bungay ◽  
Jean-Yves Chatton ◽  
Bruno Flamion ◽  
Carter C. Gibson ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Fluid Transport ◽  
Renal Tubules ◽  
Osmotic Gradient ◽  
Intercellular Spaces ◽  
Local Composition ◽  
Lateral Intercellular Spaces ◽  
Cultured Renal Epithelia ◽  
And Diffusion ◽  
Microscopic Techniques

New, optical microscopic techniques were developed to study the composition, fluid flow patterns and restrictions to diffusion in the fluid filled spaces surrounding renal epithelial cells. The prevailing theoretical model for the mechanism of isosmotic fluid transport by epithelia, the standing osmotic gradient hypothesis, predicts gradients in ion composition as well as significant restrictions to the diffusion of small solutes within the lateral intercellular spaces separating epithelial cells. Key questions about the validity of the model arise from uncertainties about the values for the hydraulic water permeability of the cell membranes and the lack of data about the composition of the fluid filling the lateral intercellular spaces. This presentation will describe measurements of the local composition, geometry and diffusion coefficients within lateral intercellular spaces of cultured renal epithelia and in the lumen of isolated, perfused renal tubules.

scholarly journals Pseudo-streaming potentials in Necturus gallbladder epithelium. II. The mechanism is a junctional diffusion potential.

1992 ◽  
Vol 99 (3) ◽  
pp. 317-338 ◽  
Author(s):  
L Reuss ◽  
B Simon ◽  
C U Cotton
Keyword(s):  
Time Course ◽  
Bathing Solution ◽  
Intercellular Spaces ◽  
Similar Time ◽  
Streaming Potentials ◽  
Osmotic Water ◽  
Lateral Intercellular Spaces ◽  
Transepithelial Voltage ◽  
Time Courses ◽  
Good Agreement

The mechanisms of apparent streaming potentials elicited across Necturus gallbladder epithelium by addition or removal of sucrose from the apical bathing solution were studied by assessing the time courses of: (a) the change in transepithelial voltage (Vms). (b) the change in osmolality at the cell surface (estimated with a tetrabutylammonium [TBA+]-selective microelectrode, using TBA+ as a tracer for sucrose), and (c) the change in cell impermeant solute concentration ([TMA+]i, measured with an intracellular double-barrel TMA(+)-selective microelectrode after loading the cells with TMA+ by transient permeabilization with nystatin). For both sucrose addition and removal, the time courses of Vms were the same as the time courses of the voltage signals produced by [TMA+]i, while the time courses of the voltage signals produced by [TBA+]o were much faster. These results suggest that the apparent streaming potentials are caused by changes of [NaCl] in the lateral intercellular spaces, whose time course reflects the changes in cell water volume (and osmolality) elicited by the alterations in apical solution osmolality. Changes in cell osmolality are slow relative to those of the apical solution osmolality, whereas lateral space osmolality follows cell osmolality rapidly, due to the large surface area of lateral membranes and the small volume of the spaces. Analysis of a simple mathematical model of the epithelium yields an apical membrane Lp in good agreement with previous measurements and suggests that elevations of the apical solution osmolality elicit rapid reductions in junctional ionic selectivity, also in good agreement with experimental determinations. Elevations in apical solution [NaCl] cause biphasic transepithelial voltage changes: a rapid negative Vms change of similar time course to that of a Na+/TBA+ bi-ionic potential and a slow positive Vms change of similar time course to that of the sucrose-induced apparent streaming potential. We conclude that the Vms changes elicited by addition of impermeant solute to the apical bathing solution are pseudo-streaming potentials, i.e., junctional diffusion potentials caused by salt concentration changes in the lateral intercellular spaces secondary to osmotic water flow from the cells to the apical bathing solution and from the lateral intercellular spaces to the cells. Our results do not support the notion of junctional solute-solvent coupling during transepithelial osmotic water flow.

scholarly journals Studies on the Electrical Potential Profile across Rabbit Ileum

1971 ◽  
Vol 57 (6) ◽  
pp. 639-663 ◽  
Author(s):  
Richard C. Rose ◽  
Stanley G. Schultz
Keyword(s):  
Amino Acids ◽  
Brush Border ◽  
Electrical Potential ◽  
Metabolic Inhibitors ◽  
Electrical Potential Difference ◽  
Intercellular Spaces ◽  
Cell Interior ◽  
Rabbit Ileum ◽  
Lateral Intercellular Spaces ◽  
Rapid Replacement

When isolated strips of mucosal rabbit ileum are bathed by physiological electrolyte solution the electrical potential difference (PD) across the brush border (ψmc) averages 36 mv, cell interior negative. Rapid replacement of Na in the mucosal solution with less permeant cations, Tris or choline, results in an immediate hyperpolarization of ψmc. Conversely, replacement of choline in the mucosal solution with Na results in an abrupt depolarization of ψmc. These findings indicate that Na contributes to the conductance across the brush border. The presence of actively transported sugars or amino acids in the mucosal solution brings about a marked depolarization of ψmc and a smaller increase in the transmural PD (Δψms). It appears that the Na influx that is coupled to the influxes of amino acids and sugars is electrogenic and responsible for the depolarization of ψmc. Under control conditions Δψms can be attributed to the depolarization of ψmc together with the presence of a low resistance transepithelial shunt, possibly the lateral intercellular spaces. However, quantitatively similar effects of amino acids on ψmc are also seen in tissues poisoned with metabolic inhibitors or ouabain. Under these conditions Δψmc is much smaller than under control conditions. Thus, the depolarization of ψmc might not account for the entire Δψms, observed in nonpoisoned tissue. An additional electromotive force which is directly coupled to metabolic processes might contribute to the normal Δψms.

Sign in / Sign up

Export Citation Format

Share Document