<i>C. perfringens</i> epsilon toxin alters fluid homeostasis in the small intestine.

<p>(A) The enteropooling assay detected small intestinal fluid accumulation induced by luminal enterotoxin. Groups of 4 mice were orally administered with different doses of <i>C. botulinum</i> C2 toxin and intestinal fluid was determined 6 hours after oral administration. The results shown are the mean±standard error of the mean. (B) Epsilon toxin of <i>C. perfringens</i> altered fluid homeostasis in the mouse small intestine. Enteropooling was measured in groups of 4 mice treated with toxin (1,000 LD₅₀) or vehicle solution 2 and 6 h after oral administration. The results are expressed as the mean±standard error of the mean. (C) Epsilon toxin of <i>C. perfringens</i> produced fluid accumulation in mouse intestinal loops. Vehicle solution with or without 1,000 LD₅₀ of toxin were injected in ligated ileal segments. The loops were excised 3 hours after injection of the toxin and intestinal water was determined gravimetrically. Each point represents the mean±standard error. (D) Basal absorption of water by the mouse small intestine was diminished by <i>C. perfringens</i> epsilon toxin when measured by the single-pass perfusion method. Perfusion began with an equilibration period of 45 min. Then, Ringer solution containing 500 LD₅₀/ml of epsilon toxin or Ringer solution alone was perfused and after 60 minutes four 15-min samples were collected. The volume of each sample was determined. Each mouse was killed at the end of the perfusion, and the segment of jejunum was removed and its length measured. The absorbed or secreted volume was calculated as collected volume minus perfused volume and expressed per centimeter of perfused bowel per minute. Data were relativized to the value obtained at time 15. Changes become statistically significant after 45 minutes of toxin delivery (<i>P</i><0.05).