pH regulation in ileum: Na(+)-H+ and Cl(-)-HCO3- exchange in isolated crypt and villus cells
Abstract
Current evidence suggests that intestinal crypt and villus cells have different functions in electrolyte transport. To study the regulation of transporters, we isolated and separated these two cell types. This was accomplished by sequential collection of enterocytes from rabbit ileal loops incubated with buffered solutions of calcium chelators. Alkaline phosphatase and thymidine kinase activity, sodium-glucose cotransport, and morphological criteria were used to determine cell separation. Cell viability was evaluated with trypan blue exclusion, leucine incorporation into protein, and morphological features. The role of Na(+)-H+ and Cl(-)-HCO3- exchange in the regulation of intracellular pH was analyzed using an intracellular pH sensitive dye, BCECF. Removal of external Na+ or the addition of amiloride resulted in acidification of both crypt and villus cells. Removal of Cl- or the addition of DIDS resulted in alkalinization of both cell types. The cells could be acidified with NH4Cl, and recovery from this acid load was dependent on Na+ and inhibited by amiloride. Similarly, the cells could be alkalinized with propionate and recovery was Cl- dependent and DIDS sensitive. These data are consistent with the presence of Na(+)-H+ and Cl(-)-HCO3- exchange in both crypt and villus cells. Both exchanges appear to be involved in the regulation of basal pH as well as in recovery from alterations in intracellular pH. Having demonstrated the presence of Na(+)-H+ and Cl(-)-HCO3- exchange…
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Coupled NaCl absorption is achieved by the dual operation of Na-H and Cl-HCO3 exchangers in the brush border membrane of villus cells, and their regulation is mediated by intracellular pH.
“For example, coupled NaCl absorption is achieved by the dual operation of Na-H and Cl-HCO3 exchangers in the BBM of villus cells, and their regulation is mediated by intracellular pH [51,52].”
From Regulation of Enterocyte Brush Border Membrane Primary Na-Absorptive Transporters in Human Intestinal Organoid-Derived Monolayers (2024) · cites this paper as [52]
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Palaniappan, B., Manoharan, P., Arthur, S., Singh, S., Murughiyan, U., & Sundaram, U. (2019) · Physiological Reports · doi:10.14814/phy2.14086 · Cited by 3 · see citing works
Self-citationHaynes, J., Palaniappan, B., Crutchley, J. M., & Sundaram, U. (2024) · Cells · doi:10.3390/cells13191623 · Cited by 2 · see citing works
“For example, coupled NaCl absorption is achieved by the dual operation of Na-H and Cl-HCO 3 exchangers in the BBM of villus cells, and their regulation is mediated by intracellular pH [51,52].”
BackgroundSelf-citation
- Authors
- Sundaram, U., Knickelbein, R. G., & Dobbins, J. W.
- Affiliations
- Yale University (US)
- ORCID
- Sundaram, U.
- Venue
- American Journal of Physiology-Gastrointestinal and Liver Physiology
- Publisher
- American Physiological Society
- Published
- 1991-03-01
- Volume
- 260
- Issue
- 3
- Pages
- G440-G449
- ISSN
- 0193-1857 (ISSN-L)
- 1522-1547
- OpenAlex
- W2098576078
- Cited by
- 70
- References
- 0
- Citations by year
- 2024: 1 · 2022: 1 · 2021: 3 · 2020: 2 · 2019: 6 · 2014: 1 · 2012: 2
- FWCI
- 1.59
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- American Journal of Physiology-Gastrointestinal and Liver Physiology (publishedVersion)
- PubMed (publishedVersion)
- Funders
- National Institutes of Health (5r01am031969-03)
- National Institute of Diabetes and Digestive and Kidney Diseases (DK-34989, P30DK034989)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Ion Transport and Channel Regulation
- Health Sciences › Medicine › Gastroenterology › Gastrointestinal motility and disorders
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Digestive system and related health
- Keywords
- intracellular pH regulation, Na+/H+ exchange, Cl-/HCO3- exchange, enterocytes, cell isolation, amiloride, DIDS, alkaline phosphatase, thymidine kinase, sodium-glucose cotransport, propionate, chloride transport, second messengers
- MeSH terms
- Alkaline Phosphatase, Amiloride, Ammonium Chloride, Animals, Bicarbonates, Carrier Proteins, Chlorides, Epithelium, Hydrogen-Ion Concentration, Ileum, Kinetics, Leucine, Methylglucosides, Microscopy, Electron, Muscle, Smooth, Rabbits, 4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid, Sodium, Protein Biosynthesis, 4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid, Sodium-Hydrogen Exchangers, 3-O-Methylglucose, Chloride-Bicarbonate Antiporters, In Vitro Techniques
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