Effect of chronic inflammation on electrolyte transport in rabbit
ileal villus and crypt cells.
Sundaram, Uma, and A. Brian West.
Departments of Medicine and Pathology, Yale University School of
Medicine, New Haven, Connecticut
APStracts 3:0179G, 1996.
The effect of chronic inflammation on electrolyte transport in rabbit
ileal villus and crypt cells was determined utilizing a rabbit model
of chronic ileitis. In both cells, Na:H exchange was monitored by
following recovery from an acid load and Cl:HCO3 exchange was
monitored by following recovery from an alkaline load. In villus
cells, recovery from an acid load was not affected, however, recovery
from an alkaline was slowed. These data suggest that chronic
inflammation inhibits Cl:HCO3 exchange in villus cells. In contrast,
in crypt cells, recovery from an alkaline load was unaffected while
recovery from an acid load was accelerated. These data suggest that
chronic inflammation stimulates Na:H exchange in crypt cells.
Inhibition of Cl:HCO3 exchange in villus cells would be expected to
inhibit coupled NaCl absorption which occurs by the coupling of BBM
Na:H and Cl:HCO3 exchange. Stimulation of Na:H exchange in crypt
cells, known to be present only on the BLM, alkalinizes the cell.
This alkalinization may stimulate the BBM Cl:HCO3 exchange resulting
in HCO3 secretion. Thus, these unique alterations in transporter
activity suggest that different endogenous immune-inflammatory
mediators may have differing effects on specific transporters in
villus and crypt cells in the chronically inflamed ileum.
Received 13 May 1996; accepted in final form 9 September 1996.
APS Manuscript Number G193-6.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 19 September 1996