Skip to main content
NCBI home page
Biophysical Journal logoLink to Biophysical Journal
. 1968 Nov;8(11):1211–1227. doi: 10.1016/S0006-3495(68)86551-8

Potential Responses of Nutrient Membrane of Frog's Stomach to Step Changes in External K+ and Cl- Concentrations

S G Spangler, W S Rehm
PMCID: PMC1367690  PMID: 5696208

Abstract

With an in vitro chamber method experiments were performed to determine the relative ionic conductances of the nutrient membrane (membrane facing muscularis mucosa). The concentration of a given ion in the nutrient bathing solution was changed, and the ensuing time course of the change in transmucosal potential difference (PD) was recorded. Changing K+ from 4 to 79 mM produced a response in PD which occurred markedly faster than the response for the reverse change, and similar results were obtained by changing the Cl- concentration. It was found that these differences were predicted by the analysis of an idealized model consisting of a membrane in series with a diffusion barrier. When both the K+ and Cl- were changed, such that the product of their concentrations remained constant, the time courses of the responses were again similiar to those predicted on the basis of the model. From the magnitudes of the total PD responses it is shown that in the presence of a 4 mM K+ nutrient solution, the conductivity of the nutrient membrane appears to be entirely due to the K+ and Cl- conductances, the K+ conductance being about twice that of the Cl-. It is also shown that with a 79 mM K+ nutrient solution the parameters of the membrane were changed such that the conductances of the two ions were approximately equal. The time constant for diffusion of KCl or NaCl across the barrier consisting of the submucosa, muscularis mucosa, and lamina propria is about 1 min.

Full text

PDF
1211

Selected References

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

  1. Canosa C. A., Rehm W. S. Microelectrode studies of dog's gastric mucosa. Biophys J. 1968 Apr;8(4):415–430. doi: 10.1016/S0006-3495(68)86497-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. DAVENPORT H. W., ALZAMORA F. Sodium, potassium, chloride, and water in frog gastric mucosa. Am J Physiol. 1962 Apr;202:711–715. doi: 10.1152/ajplegacy.1962.202.4.711. [DOI] [PubMed] [Google Scholar]
  3. HARRIS J. B., EDELMAN I. S. CHEMICAL CONCENTRATION GRADIENTS AND ELECTRICAL PROPERTIES OF GASTRIC MUCOSA. Am J Physiol. 1964 Apr;206:769–782. doi: 10.1152/ajplegacy.1964.206.4.769. [DOI] [PubMed] [Google Scholar]
  4. HODGKIN A. L., HOROWICZ P. The influence of potassium and chloride ions on the membrane potential of single muscle fibres. J Physiol. 1959 Oct;148:127–160. doi: 10.1113/jphysiol.1959.sp006278. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. KIDDER G. W., 3rd, CEREIJIDO M., CURRAN P. F. TRANSIENT CHANGES IN ELECTRICAL POTENTIAL DIFFERENCES ACROSS FROG SKIN. Am J Physiol. 1964 Oct;207:935–940. doi: 10.1152/ajplegacy.1964.207.4.935. [DOI] [PubMed] [Google Scholar]
  6. REHM W. S. Acid secretion, resistance, short-circuit current, and voltage-clamping in frog's stomach. Am J Physiol. 1962 Jul;203:63–72. doi: 10.1152/ajplegacy.1962.203.1.63. [DOI] [PubMed] [Google Scholar]
  7. Rehm W. S. Electrogenic mechanisms of the frog's gastric mucosa. Ann N Y Acad Sci. 1966 Jul 14;137(2):591–605. doi: 10.1111/j.1749-6632.1966.tb50184.x. [DOI] [PubMed] [Google Scholar]
  8. Rehm W. S. Ion permeability and electrical resistance of the frog's gastric mucosa. Fed Proc. 1967 Sep;26(5):1303–1313. [PubMed] [Google Scholar]

Articles from Biophysical Journal are provided here courtesy of The Biophysical Society

RESOURCES