TY - JOUR
T1 - Effects of luminal hyperosmolality on cellular and paracellular ion transport pathways in Necturus antrum
AU - Soybel, David I.
AU - Ashley, Stanley W.
AU - DeSchryver-Kecskemeti, Katherine
AU - Cheung, Laurence Y.
N1 - Funding Information:
Address requests for reprints to: Laurence Y. Cheung, M.D.. Department of Surgery, University of Kansas Medical Center, 39th and Rainbow Boulevard, Kansas City, Kansas 66103. This work was supported by the Medical Research Service of the Veterans Administration and by grants AM25998-05 and AM07178-0 from the National Institutes of Health. 0 1987 by the American Gastroenterological Association 0016-5085187/$3.50
PY - 1987/9
Y1 - 1987/9
N2 - Using microelectrode techniques, the electrical properties of the cell membranes and paracellular pathway of the surface epithelium in Necturus antrum were studied under control conditions and during exposure to mucosal solutions made hyperosmotic by addition of sucrose or urea. Sucrose (500 mmol/kg) significantly decreased apical membrane resistances (Ra, from 5501 ± 841 to 3789 ± 597 Ω · cm2, p < 0.01), and basolateral membrane resistances (Rb, from 3805 ± 646 to 2594 ± 429 Ω · cm2, p < 0.05). The paracellular pathway resistance (Rs) increased significantly from 720 ± 57 to 822 ± 71 Ω · cm2 (p < 0.001). Urea (500 mmol/kg) more markedly diminished the apical and basolateral resistances (Ra, from 4303 ± 663 to 1914 ± 286 Ω · cm2, p < 0.001; and Rb, from 2600 ± 474 to 1034 ± 213, p < 0.001). In contrast to sucrose, urea-containing solutions significantly decreased Rs (from 682 ± 78 to 398 ± 57 Ω · cm2, p < 0.001). Electron micrographs revealed dilatation of lateral intercellular spaces and disruption of desmosomes in tissues exposed to urea, but no visible alterations in tissues exposed to solutions containing sucrose. The resistance of the cellular pathway to ion permeation was thus diminished during exposure to both solutes. In contrast, changes in resistance of the paracellular pathway appeared to depend on the effects of each solute on dimensions and structures of the intercellular pathways.
AB - Using microelectrode techniques, the electrical properties of the cell membranes and paracellular pathway of the surface epithelium in Necturus antrum were studied under control conditions and during exposure to mucosal solutions made hyperosmotic by addition of sucrose or urea. Sucrose (500 mmol/kg) significantly decreased apical membrane resistances (Ra, from 5501 ± 841 to 3789 ± 597 Ω · cm2, p < 0.01), and basolateral membrane resistances (Rb, from 3805 ± 646 to 2594 ± 429 Ω · cm2, p < 0.05). The paracellular pathway resistance (Rs) increased significantly from 720 ± 57 to 822 ± 71 Ω · cm2 (p < 0.001). Urea (500 mmol/kg) more markedly diminished the apical and basolateral resistances (Ra, from 4303 ± 663 to 1914 ± 286 Ω · cm2, p < 0.001; and Rb, from 2600 ± 474 to 1034 ± 213, p < 0.001). In contrast to sucrose, urea-containing solutions significantly decreased Rs (from 682 ± 78 to 398 ± 57 Ω · cm2, p < 0.001). Electron micrographs revealed dilatation of lateral intercellular spaces and disruption of desmosomes in tissues exposed to urea, but no visible alterations in tissues exposed to solutions containing sucrose. The resistance of the cellular pathway to ion permeation was thus diminished during exposure to both solutes. In contrast, changes in resistance of the paracellular pathway appeared to depend on the effects of each solute on dimensions and structures of the intercellular pathways.
UR - https://www.scopus.com/pages/publications/0023196960
UR - https://www.scopus.com/pages/publications/0023196960#tab=citedBy
U2 - 10.1016/0016-5085(87)90906-1
DO - 10.1016/0016-5085(87)90906-1
M3 - Article
C2 - 3609656
AN - SCOPUS:0023196960
SN - 0016-5085
VL - 93
SP - 456
EP - 465
JO - Gastroenterology
JF - Gastroenterology
IS - 3
ER -