title: Early systemic inflammatory response in mice after a single oral gavage with live Escherichia coli is evidenced by increased TNF-alpha and nitric oxide production.
abstract: Twenty-four female BALB/c mice were orally inoculated with 10(8) CFU Escherichia coli ATCC 25922 and euthanized 2.5, 7, 13 and 25 h post-inoculation. The levels of organ nitric oxide (NO) and plasma endotoxin, TNF-alpha and nitrite/nitrate (NO(x)) were compared to those found in sham-inoculated mice, to evaluate systemic host-response to a low-level oral exposure to Gram-negative bacteria. Organ bacterial culture and immunohistochemistry for iNOS were performed on lungs, liver, kidneys and brain from all mice. Organ NO and plasma TNF-alpha levels were higher in E. coli-inoculated animals, but no differences were detected in plasma endotoxin levels, NO(x) or iNOS immunostaining for any of the animal groups. Single oral gavage with live E. coli stimulates an early systemic immune response in clinically healthy mice as evidenced by increased plasma TNF-alpha and organ NO levels, but bacteremia and endotoxemia are not related to this inflammatory response.
authors.affiliation: Veterinary Faculty Small Animal Clinic, University of Ljubljana, Gerbičeva 60, 1115 Ljubljana, Slovenia. anemec@ucdavis.edu
authors.forename: Ana
authors.initials: A
authors.lastname: Nemec
authors.forename: Aleš
authors.initials: A
authors.lastname: Jerin
authors.forename: Irena
authors.initials: I
authors.lastname: Zdovc
authors.forename: Tomaž
authors.initials: T
authors.lastname: Budefeld
authors.forename: Frank J M
authors.initials: FJ
authors.lastname: Verstraete
authors.forename: Damijan
authors.initials: D
authors.lastname: Eržen
authors.forename: Marjeta
authors.initials: M
authors.lastname: Sentjurc
authors.forename: Milan
authors.initials: M
authors.lastname: Petelin
authors.forename: Tina
authors.initials: T
authors.lastname: Hitti
authors.forename: Zlatko
authors.initials: Z
authors.lastname: Pavlica
mesh_terms: D000818:Animals; D001921:Brain / Q000201:enzymology / Q000276:immunology; D004927:Escherichia coli Infections / Q000276:immunology*; D005260:Female; D007150:Immunohistochemistry; D007668:Kidney / Q000201:enzymology / Q000276:immunology; D008099:Liver / Q000201:enzymology / Q000276:immunology; D008168:Lung / Q000201:enzymology / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D009569:Nitric Oxide / Q000097:blood / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II; D013047:Specific Pathogen-Free Organisms; D018746:Systemic Inflammatory Response Syndrome / Q000382:microbiology*; D014409:Tumor Necrosis Factor-alpha / Q000097:blood / Q000378:metabolism*
chemical_list: D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II