Colonic structural and ion transport abnormalities in suckling rabbits infected with Escherichia coli K12

Abstract

Background: Escherichia coli K12 is a laboratory strain considered nonpathogenic. The purpose of this study was to examine the effect of E. coli K12 infection on colonic structure and function. Methods: Suckling rabbits were infected at 10 days of age with 6 x 109 CFU E. coli by intragastric inoculation and were examined 4 to 5 days later. Segments of ileum and proximal and distal colon were removed for light and electron microscopy, and NaCl transport was examined in vitro under short-circuited conditions in Ussing chambers. Results: Infection did not cause weight loss or diarrhea. Colonic mucosa was inflamed with infiltration by polymorphonuclear neutrophils mainly in the lamina propria. T..