Gastrointestinal tract electrolyte transport

Cooke, H J, Reddix, R.A., 1994 Neural regulation of intestinal electrolyte transport In Johnson, L.R. (Ed ), Physiology of the gastrointestinal tract. Raven Press, New York, (NY), pp. 2083-2132. 

Increased motility of the gastrointestinal tract and decreased absorption of fluid are major factors in diarrhea. Antidiarrheal drugs include antimotility agents, adsorbents, and drugs that modify fluid and electrolyte transport (Figure 24.8). 

In the normal adult, 7-8 litres of of water and electrolytes are secreted daily into the gastrointestinal tract. This, together with dietary fluid, is absorbed by epithehal cells in the small and large bowel. Water follows the osmotic gradients which result from shifts of electrolytes across the intestinal epithelium, and sodium and chloride transport mechanisms are central to the causation and management of diarrhoea, especially that caused by bacteria and viruses. The energy for the process is provided by the activity of Na /K ATPase. 

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