Effects of nitric oxide in 5-hydroxytryptamine-, cholera toxin-, enterotoxigenic Escherichia coli- and Salmonella Typhimurium-induced secretion in the porcine small intestine.
The effects of nitric oxide (NO) in the secretory response to the endogenous secretagogue 5-hydroxytryptamine (5-HT), the enterotoxins heat-labile enterotoxigenic Escherichia coli (ETEC) toxin (LT) and cholera toxin (CT), and various cultures of ETEC and Salmonella serotype Typhimurium in the porcine small intestine (Sus scrofa) were investigated. In anaesthetized pigs, jejunal tied-off loops were instilled with 5-HT, LT, CT, various cultures of ETEC or S. Typhimurium. Pigs were given intravenously isotonic saline or isotonic saline containing the NO synthase inhibitor, Nomega-nitro-L-arginine methyl ester (L-NAME). L-NAME significantly induced an increased fluid accumulation in loops induced by 5-HT, ETEC and stn-mutated S. Typhimurium. Fluid accumulation in loops instilled with wild-type S. Typhimurium was increased by L-NAME, although not significantly, while there was no effect on fluid accumulation induced by an invH-mutated isogenic strain. No significant effect of L-NAME was observed on the fluid accumulation induced by the purified enterotoxins LT and CT. The results also demonstrated a relatively large difference in the ability to induce fluid accumulation between the bacteria strains. Diastolic, systolic and mean blood pressures were significantly increased and the body temperature was significantly decreased in groups of pigs treated with L-NAME. In conclusion, the results suggest that NO has a proabsorptive effect in the intact porcine jejunum and is involved in the systemic vascular tone.
Grøndahl
Marie Louise
ML
Department of Basic Animal and Veterinary Sciences, The Royal Veterinary and Agricultural University, Grønnegårdsvej 7, DK-1870 Frederiksberg C, Denmark.
Unmack
Martin Andreas
MA
Ragnarsdóttir
Helga Berglind
HB
Hansen
Mark Berner
MB
Olsen
John Elmerdahl
JE
Skadhauge
Erik
E
D000818:Animals; D000890:Anti-Infective Agents / Q000378:metabolism; D001794:Blood Pressure; D001831:Body Temperature; D002772:Cholera Toxin / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects* / Q000378:metabolism / Q000472:pathogenicity*; D005260:Female; D007421:Intestine, Small / Q000187:drug effects* / Q000382:microbiology*; D009154:Mutation; D019331:NG-Nitroarginine Methyl Ester / Q000378:metabolism / Q000494:pharmacology; D009474:Neurons / Q000378:metabolism; D009569:Nitric Oxide / Q000494:pharmacology*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D020033:Protein Isoforms; D012480:Salmonella Infections; D012486:Salmonella typhimurium / Q000187:drug effects* / Q000378:metabolism / Q000472:pathogenicity*; D012701:Serotonin / Q000494:pharmacology*; D013552:Swine; D013997:Time Factors
D000890:Anti-Infective Agents; D020033:Protein Isoforms; D009569:Nitric Oxide; D012701:Serotonin; D002772:Cholera Toxin; D019001:Nitric Oxide Synthase; D019331:NG-Nitroarginine Methyl Ester