Altered intestinal motility precedes diarrhea during Escherichia coli enteric infection

Changes in ileal and colonic myoelectric activity during the course of enteric infection of rabbits with the enteropathogenic Escherichia coli strain RDEC-1 were determined and related to microbiological, histological, and clinical parameters of disease. Rabbits were grouped into early, peak, and late stages of infection based on fecal shedding of bacteria. Weight loss and an increase in prolonged spike bursts (both action potential complexes and ileal migrating action potential complexes) developed early in infection, before the onset of diarrhea. Loose stools subsequently developed coincident with maximal numbers of action potential complexes. The myoelectric responses correlated better with mucosal enteroadherence of bacteria than with luminal colonization. These data demonstrate that, in this animal model of enteroadherent bacterial infection of the intestine, changes in intestinal myoelectric activity precede the onset of clinical diarrhea. In addition, bacterial adherence to the intestinal mucosa appears to be important in eliciting the abnormal myoelectric responses.