The effect of enterohemorrhagic Escherichia coli O157:H7 on intestinal structure and solute transport in rabbits.
BACKGROUND
The effect of enterohemorrhagic Escherichia coli O157:H7 infection on intestinal morphology and solute transport was examined.


METHODS
New Zealand white rabbits, aged 10 days, were infected with E. coli strain EDL933 (O157:H7 containing the 60-megadalton plasmid-encoding adhesion factors VT1 and VT2) and compared with controls. Small and large intestinal histology and solute transport were studied 5 days after inoculation. Ion transport in the distal colon was also examined in animals infected with different strains encoding a combination of pathogenic factors.


RESULTS
Infection with EDL933 induced diarrhea and mucosal disease in the colon, inhibited colonic Na+ absorption, and stimulated of Cl- secretion, but had no impact on the small intestine. Infection with strains A7785-C3A (O157:H7, plasmid-, VT1+, VT2+) and 85-170 (O157:H7, plasmid+, VT-) induced similar transport changes to EDL933. C600/1 (E. coli K-12, plasmid+, VT1+) decreased Na+ and Cl- absorption only.


CONCLUSIONS
Abnormalities of colonic structure and ion transport could account for diarrhea production, but pathogenic factors other than the 60-megadalton plasmid-encoding adhesion factor and verotoxins appear to be involved in enterohemorrhagic E. coli infection.
Li
Z
Z
Department of Pediatrics and Child Health, Children's Hospital, Camperdown, Australia.
Bell
C
C
Buret
A
A
Robins-Browne
R
R
Stiel
D
D
O'Loughlin
E
E
D000818:Animals; D002712:Chlorides / Q000378:metabolism*; D003106:Colon / Q000378:metabolism / Q000473:pathology; D004195:Disease Models, Animal; D004927:Escherichia coli Infections / Q000378:metabolism* / Q000473:pathology*; D007082:Ileum / Q000378:metabolism; D066298:In Vitro Techniques; D007413:Intestinal Mucosa / Q000473:pathology*; D017136:Ion Transport; D011817:Rabbits; D012964:Sodium / Q000378:metabolism*
D002712:Chlorides; D012964:Sodium