Lr. Schiller et al., GLUCOSE-STIMULATED SODIUM-TRANSPORT BY THE HUMAN INTESTINE DURING EXPERIMENTAL CHOLERA, Gastroenterology, 112(5), 1997, pp. 1529-1535
Background & Aims: Net sodium absorption from oval rehydration solutio
n is increased by both glucose-sodium cotransport and solvent drag. Th
e aim of this study was to measure the relative importance of glucose-
sodium cotransport and solvent drag in the stimulation of net sodium a
bsorption by oral rehydration solution. Methods: Total intestinal perf
usion was used in normal subjects with and without intrajejunal choler
a toxin using three test solutions containing 100 mmol/L sodium and ei
ther 100 mmol/L mannitol (control), 100 mmol/L glucose, or no addition
al solute (hypotonic solution). The increase in sodium absorption grea
ter than control with hypotonic solution represented sodium absorption
stimulated by solvent drag; the further increase in sodium absorption
induced by glucose, greater than that noted with the hypotonic soluti
on, represented sodium absorption stimulated by cotransport. Results:
Without cholera toxin, solvent drag and cotransport promoted sodium ab
sorption at rates of 62 and 33 mmol/h, respectively. With cholera toxi
n, solvent drag and cotransport promoted sodium absorption at rates of
44 and 71 mmol/h, respectively. Conclusions: Net sodium absorption ca
used by cotransport increased move than twofold after exposure of the
intestine to cholera toxin (P < 0.003). This could be mediated by incr
eased cotransport, a change in the stoichiometry of cotransport, or an
increase in chloride permeability.