Effects of cations and pH on apical membrane potential of in vitro Necturus antrum

Michael Rutten, R. Delcore, D. I. Soybel, C. D. Moore, L. Y. Cheung

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

The surface epithelial cells of the gastric mucosa transport Na+ from lumen to serosa. The first step in this process is the entry of Na+ through an amiloride-sensitive Na+ channel at the apical membrane. The exact function(s) of this Na+ transport are unknown, but it has been suggested that it might help the stomach to withstand an acid load. The present study was undertaken to examine the effects of low luminal pH and the alkali cations Li+, K+, Rb+, and Cs+ on the amiloride-sensitive Na+ permeability of the apical membrane of Necturus antral cells by measuring the changes in apical membrane voltage (V(mc)) using conventional microelectrode techniques. Isosmolar replacement of luminal NaCl (pH 7.25) with LiCl caused a depolarization of the V(mc), a decrease in transepithelial resistance (R(t)), and an increase in the transepithelial potential (V(ms)), whereas replacement with KCl, RbCl, or CsCl caused a hyperpolarization of the V(mc), an increase in R(t), and a decrease in the V(ms). Luminal acidification from pH 7.25 to pH 3.00 caused very similar changes with all the cation solutions tested, hyperpolarizing the V(mc), increasing R(t), and reducing the V(ms) to near 0 mV. Acidification of the luminal NaCl solution from pH 7.25 to pH 2.00 caused a progressive hyperpolarization of the V(mc) similar to the effects seen with luminal amiloride (10-4 M) in pH 7.25 NaCl solutions or luminal Na+-free (N-methyl-D-glucamine) Ringer at pH 7.25. These results demonstrate that 1) of the cations tested only Li+ can substitute for Na+ in maintaining the V(mc), and 2) external H ions (low luminal pH) block cation permeability of the apical membrane.

Original languageEnglish (US)
JournalAmerican Journal of Physiology - Gastrointestinal and Liver Physiology
Volume256
Issue number4
StatePublished - 1989
Externally publishedYes

Fingerprint

Necturus
Membrane Potentials
Cations
Amiloride
Membranes
Permeability
In Vitro Techniques
Serous Membrane
Alkalies
Microelectrodes
Gastric Mucosa
Stomach
Epithelial Cells
Ions

ASJC Scopus subject areas

  • Physiology
  • Gastroenterology

Cite this

Effects of cations and pH on apical membrane potential of in vitro Necturus antrum. / Rutten, Michael; Delcore, R.; Soybel, D. I.; Moore, C. D.; Cheung, L. Y.

In: American Journal of Physiology - Gastrointestinal and Liver Physiology, Vol. 256, No. 4, 1989.

Research output: Contribution to journalArticle

Rutten, Michael ; Delcore, R. ; Soybel, D. I. ; Moore, C. D. ; Cheung, L. Y. / Effects of cations and pH on apical membrane potential of in vitro Necturus antrum. In: American Journal of Physiology - Gastrointestinal and Liver Physiology. 1989 ; Vol. 256, No. 4.
@article{991d6edc9c18446ca492b9f04d833938,
title = "Effects of cations and pH on apical membrane potential of in vitro Necturus antrum",
abstract = "The surface epithelial cells of the gastric mucosa transport Na+ from lumen to serosa. The first step in this process is the entry of Na+ through an amiloride-sensitive Na+ channel at the apical membrane. The exact function(s) of this Na+ transport are unknown, but it has been suggested that it might help the stomach to withstand an acid load. The present study was undertaken to examine the effects of low luminal pH and the alkali cations Li+, K+, Rb+, and Cs+ on the amiloride-sensitive Na+ permeability of the apical membrane of Necturus antral cells by measuring the changes in apical membrane voltage (V(mc)) using conventional microelectrode techniques. Isosmolar replacement of luminal NaCl (pH 7.25) with LiCl caused a depolarization of the V(mc), a decrease in transepithelial resistance (R(t)), and an increase in the transepithelial potential (V(ms)), whereas replacement with KCl, RbCl, or CsCl caused a hyperpolarization of the V(mc), an increase in R(t), and a decrease in the V(ms). Luminal acidification from pH 7.25 to pH 3.00 caused very similar changes with all the cation solutions tested, hyperpolarizing the V(mc), increasing R(t), and reducing the V(ms) to near 0 mV. Acidification of the luminal NaCl solution from pH 7.25 to pH 2.00 caused a progressive hyperpolarization of the V(mc) similar to the effects seen with luminal amiloride (10-4 M) in pH 7.25 NaCl solutions or luminal Na+-free (N-methyl-D-glucamine) Ringer at pH 7.25. These results demonstrate that 1) of the cations tested only Li+ can substitute for Na+ in maintaining the V(mc), and 2) external H ions (low luminal pH) block cation permeability of the apical membrane.",
author = "Michael Rutten and R. Delcore and Soybel, {D. I.} and Moore, {C. D.} and Cheung, {L. Y.}",
year = "1989",
language = "English (US)",
volume = "256",
journal = "American Journal of Physiology - Renal Fluid and Electrolyte Physiology",
issn = "1931-857X",
publisher = "American Physiological Society",
number = "4",

}

TY - JOUR

T1 - Effects of cations and pH on apical membrane potential of in vitro Necturus antrum

AU - Rutten, Michael

AU - Delcore, R.

AU - Soybel, D. I.

AU - Moore, C. D.

AU - Cheung, L. Y.

PY - 1989

Y1 - 1989

N2 - The surface epithelial cells of the gastric mucosa transport Na+ from lumen to serosa. The first step in this process is the entry of Na+ through an amiloride-sensitive Na+ channel at the apical membrane. The exact function(s) of this Na+ transport are unknown, but it has been suggested that it might help the stomach to withstand an acid load. The present study was undertaken to examine the effects of low luminal pH and the alkali cations Li+, K+, Rb+, and Cs+ on the amiloride-sensitive Na+ permeability of the apical membrane of Necturus antral cells by measuring the changes in apical membrane voltage (V(mc)) using conventional microelectrode techniques. Isosmolar replacement of luminal NaCl (pH 7.25) with LiCl caused a depolarization of the V(mc), a decrease in transepithelial resistance (R(t)), and an increase in the transepithelial potential (V(ms)), whereas replacement with KCl, RbCl, or CsCl caused a hyperpolarization of the V(mc), an increase in R(t), and a decrease in the V(ms). Luminal acidification from pH 7.25 to pH 3.00 caused very similar changes with all the cation solutions tested, hyperpolarizing the V(mc), increasing R(t), and reducing the V(ms) to near 0 mV. Acidification of the luminal NaCl solution from pH 7.25 to pH 2.00 caused a progressive hyperpolarization of the V(mc) similar to the effects seen with luminal amiloride (10-4 M) in pH 7.25 NaCl solutions or luminal Na+-free (N-methyl-D-glucamine) Ringer at pH 7.25. These results demonstrate that 1) of the cations tested only Li+ can substitute for Na+ in maintaining the V(mc), and 2) external H ions (low luminal pH) block cation permeability of the apical membrane.

AB - The surface epithelial cells of the gastric mucosa transport Na+ from lumen to serosa. The first step in this process is the entry of Na+ through an amiloride-sensitive Na+ channel at the apical membrane. The exact function(s) of this Na+ transport are unknown, but it has been suggested that it might help the stomach to withstand an acid load. The present study was undertaken to examine the effects of low luminal pH and the alkali cations Li+, K+, Rb+, and Cs+ on the amiloride-sensitive Na+ permeability of the apical membrane of Necturus antral cells by measuring the changes in apical membrane voltage (V(mc)) using conventional microelectrode techniques. Isosmolar replacement of luminal NaCl (pH 7.25) with LiCl caused a depolarization of the V(mc), a decrease in transepithelial resistance (R(t)), and an increase in the transepithelial potential (V(ms)), whereas replacement with KCl, RbCl, or CsCl caused a hyperpolarization of the V(mc), an increase in R(t), and a decrease in the V(ms). Luminal acidification from pH 7.25 to pH 3.00 caused very similar changes with all the cation solutions tested, hyperpolarizing the V(mc), increasing R(t), and reducing the V(ms) to near 0 mV. Acidification of the luminal NaCl solution from pH 7.25 to pH 2.00 caused a progressive hyperpolarization of the V(mc) similar to the effects seen with luminal amiloride (10-4 M) in pH 7.25 NaCl solutions or luminal Na+-free (N-methyl-D-glucamine) Ringer at pH 7.25. These results demonstrate that 1) of the cations tested only Li+ can substitute for Na+ in maintaining the V(mc), and 2) external H ions (low luminal pH) block cation permeability of the apical membrane.

UR - http://www.scopus.com/inward/record.url?scp=0024512307&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0024512307&partnerID=8YFLogxK

M3 - Article

C2 - 2539740

AN - SCOPUS:0024512307

VL - 256

JO - American Journal of Physiology - Renal Fluid and Electrolyte Physiology

JF - American Journal of Physiology - Renal Fluid and Electrolyte Physiology

SN - 1931-857X

IS - 4

ER -