Pathogenesis of Salmonellosis: Salmonella Exotoxins

Two Salmonella isolates were selected to study the effect of selected culture media, temperature, oxygen tension, and trypsin on release of toxin. Other efforts have been directed toward determining whether the heat labile Salmonella toxin has a direct, enterotoxic effect on the small intestine of experimental animals. Partially purified preparations of the toxin caused accumulation of fluid in ligated intestinal loops of adult rabbits. This response is blocked by heating the toxin preparation 100 C for 10 minutes or by preincubation with monospecific cholera antitoxin. In addition, we have substantiated an earlier report that immunization of rabbits with procholeragenoid will protect them against fluid loss from intestinal loop challenge with Salmonella typhimurium. The latter observation tends to support to concept that a heat labile, cholera toxin-like enterotoxin could be involved in the loss of fluid and electrolytes from the intestine during salmonellosis.