Regional differences in the effect of mucosal glucose and amino acids on ion transport in normal and cholera toxin-stimulated porcine small intestine.
BACKGROUND
This study explores regional differences in the response to mucosal D-glucose and L-amino acids in both normal intestine and intestine stimulated with cholera toxin.


METHODS
Proximal, mid and distal small intestines from 6- to 8-week-old pigs were bathed in Ussing chambers with a buffer containing 15 mM serosal glucose, and the effect of adding a cocktail giving luminal chamber concentrations of 15 mM D-glucose and 20 mM of each L-alanine, L-proline, L-lysine, L-phenylalanine, and L-glutamine on transmucosal Na+ and Cl- transport was measured.


RESULTS
In all segments of both normal and cholera toxin-treated intestine, electrogenic Na+ and electroneutral NaCl absorption were promoted. No significant differences in the net increase of Na+ and Cl- absorption between normal and cholera toxin-stimulated intestine were present. Under both conditions no segmental differences were present in the stimulated Cl- absorption, describing identical capacity for stimulated electroneutral NaCl absorption. In contrast the electrogenic Na+ absorption was, compared to the proximal part, doubled in the mid and distal parts under both conditions.


CONCLUSIONS
We conclude that mucosal D-glucose and L-amino acids stimulate electroneutral NaCl and electrogenic Na+ absorption to the same degree in normal and cholera toxin-treated small intestine. There is no segmental difference in stimulated electroneutral NaCl absorption, while electrogenic Na+ absorption is highest in mid and distal parts.
Grøndahl
M L
ML
Dept. of Anatomy and Physiology, Royal Veterinary and Agricultural University, Frederiksberg, Denmark.
Munck
L K
LK
Skadhauge
E
E
D000596:Amino Acids / Q000494:pharmacology*; D000818:Animals; D002712:Chlorides / Q000378:metabolism*; D002772:Cholera Toxin / Q000633:toxicity; D005753:Gastric Mucosa / Q000187:drug effects / Q000378:metabolism*; D005947:Glucose / Q000494:pharmacology*; D007408:Intestinal Absorption / Q000187:drug effects; D007421:Intestine, Small / Q000187:drug effects / Q000378:metabolism*; D017136:Ion Transport / Q000187:drug effects; D018408:Patch-Clamp Techniques; D012964:Sodium / Q000378:metabolism*; D013268:Stimulation, Chemical; D013552:Swine
D000596:Amino Acids; D002712:Chlorides; D002772:Cholera Toxin; D012964:Sodium; D005947:Glucose