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Ion transport in the small intestine
Jayashree Venkatasubramanian1, Mei Ao, Mrinalini C Rao
1Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois 60612, USA.
Current Opinion in Gastroenterology
|December 17, 2009
Summary
Advances in small intestinal ion transport research highlight the crucial roles of sodium-glucose cotransporter (SGLT) structure-function relationships and the paracellular pathway in diarrheal diseases. Understanding these mechanisms aids in developing targeted therapies.
Area of Science:
- Gastroenterology
- Molecular Physiology
- Cell Biology
Background:
- Previous reviews focused on duodenal bicarbonate secretion and inflammation-associated diarrhea.
- Current research emphasizes ion-coupled solute transport and the paracellular pathway in enteric infections.
Purpose of the Study:
- To review recent advances in small intestinal ion transport.
- To elucidate the cellular basis of diarrheas associated with enteric infections.
- To explore the role of the paracellular pathway in fluid transport.
Main Methods:
- Review of current literature on small intestinal ion transport.
- Analysis of cellular pathophysiology in diarrheal diseases.
- Integration of data from in-vivo animal and human studies.
Main Results:
- Increased focus on altered sodium (Na) absorptive mechanisms and paracellular pathway in diarrheal diseases.
- Continued recognition of chloride (Cl) secretory pathways, including cystic fibrosis transmembrane conductance regulator (CFTR).
- The crystal structure of the Na-galactose transporter provides insights into structure-function relationships and drug design.
Conclusions:
- Progress is being made in integrating reductionist models with complex in-vivo and human studies.
- Coordinated regulation of Na absorptive, Cl-secretory, and paracellular pathways is key to understanding small intestinal transport in health and disease.
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