title: Single oral inoculation with Escherichia coli (ATCC 25922) stimulates generalised production of nitric oxide in mice.
abstract: Nitric oxide (NO) production was investigated in the lungs, thoracic aorta, heart, liver, spleen, kidneys and brain of mice inoculated orally with Escherichia coli ATCC 25922. Detection of NO was performed by electron paramagnetic resonance (EPR) using diethyldithiocarbamate (DETC) spin trap. Nitric oxide synthase (NOS) inhibitors [nonselective: L-NAME and inducible NOS (iNOS) selective: 1400W] were used to determine the source of NO. Spin-trap only and untreated mice were included as controls. Within 2.5 hours (h) of a single oral inoculation with E. coli half of the animals had increased NO levels in all investigated organs. Thereafter the signals dropped before increasing again to reach maximal median values by 25 h in all organs of all inoculated mice. The most intense response occurred in livers, followed by aorta and lungs. Early (2.5 h) inhibition of the signal was achieved using both NOS inhibitors. L-NAME was also effective at 25 h, while 1400W-treated mice had increased NO levels beyond 7 h. The generalised increase in NO production in the short and longer term indicates a host response to E. coli administered by the oral route of infection.
authors.affiliation: Veterinary Faculty Small Animal Clinic, University of Ljubljana, Gerbiceva 60, 1115 Ljubljana, Slovenia. ana.nemec@vf.uni-lj.si
authors.forename: Ana
authors.initials: A
authors.lastname: Nemec
authors.forename: Zlatko
authors.initials: Z
authors.lastname: Pavlica
authors.forename: David A
authors.initials: DA
authors.lastname: Crossley
authors.forename: Irena
authors.initials: I
authors.lastname: Zdovc
authors.forename: Damijan
authors.initials: D
authors.lastname: Erzen
authors.forename: Marjeta
authors.initials: M
authors.lastname: Sentjurc
authors.forename: Marjana
authors.initials: M
authors.lastname: Nemec
authors.forename: Milan
authors.initials: M
authors.lastname: Petelin
mesh_terms: D000818:Animals; D004926:Escherichia coli / Q000502:physiology*; D004927:Escherichia coli Infections / Q000378:metabolism*; D005260:Female; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D011897:Random Allocation
chemical_list: D009569:Nitric Oxide; D019001:Nitric Oxide Synthase