Forty adult rabbits were inoculated with cholera vibrio toxins (endotoxin and enterotoxin) intravenously or into the operatively pre-isolated segments of the jejunum some of which remained intact. The examinations were carried out 3--5 hours after intravenous and 18--24 hours after intraintestinal inoculation of the toxins. Irrespective of the route of endotoxin inoculation, circulation disorders developed predominantly in the jejunum mucosa. Its content did not change in volume but the potassium ions concentration increased. Active hypersecretion in the epithelial cells of the jejunum mucosa was observed after inoculations of enterotoxin by both routes. It was followed by both quantitative and qualitative changes of its contents: increased concentration of potassium, sodium, chlorine ions and bicarbonates only in the ileum. Histopathological lesions in ;the jejunum mucosa were absent after inoculation of cholera vibrio toxins by both routes.