title: Enterotoxin activity of a Salmonella typhimurium of equine origin in vivo in rabbits and the effect of Salmonella culture lysates and cholera toxin on equine colonic mucosa in vitro.
abstract: To determine whether a strain of Salmonella typhimurium (UCD 1755) of equine origin had enterotoxin activity, 2 ml of a cell-free culture lysate of strain UCD 1755 and approximately 10(9) viable strain UCD 1755 organisms were inoculated into ligated small intestinal segments of rabbits. Intestinal segments inoculated with viable strain UCD 1755 organisms and those inoculated with a cell-free culture lysate of strain UCD 1755 had significant (P less than 0.05) accumulations of fluid 10 hours after inoculation when compared with ligated intestinal segments either inoculated with sterile brain-heart infusion broth or left empty. There was not a statistically significant difference between fluid accumulation of intestinal segments inoculated with viable strain UCD 1755 and that of segments inoculated with a cell-free culture lysate of strain UCD 1755. The responses of equine colonic mucosa to culture filtrates of 2 strains of salmonella typhimurium (UCD 1755 and SL 1027) and purified cholera toxin were studied in vitro. Isolated smaples of colonic mucosa were incubated for 4 hours at 37 C in Krebs-Henseleit bicarbonate buffer (KHB) alone, KHB plus culture lysate of strain UCD 1755, KHB plus culture lysate of strain SL 1027, and KHB plus 1 microgram of cholera toxin/ml. Cyclic adenosine monophosphate (cAMP) content of each sample was determined.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000818:Animals; D001427:Bacterial Toxins / Q000633:toxicity*; D002478:Cells, Cultured; D002772:Cholera Toxin / Q000633:toxicity*; D003106:Colon / Q000187:drug effects* / Q000378:metabolism; D000242:Cyclic AMP / Q000378:metabolism; D004731:Endotoxins; D004768:Enterotoxins / Q000633:toxicity*; D006734:Horse Diseases / Q000382:microbiology; D006736:Horses; D066298:In Vitro Techniques; D007413:Intestinal Mucosa / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D011817:Rabbits; D012481:Salmonella Infections, Animal / Q000382:microbiology; D012486:Salmonella typhimurium / Q000302:isolation & purification*
chemical_list: D001427:Bacterial Toxins; D004731:Endotoxins; D004768:Enterotoxins; C027952:salmonella toxin; D002772:Cholera Toxin; D000242:Cyclic AMP