The role of neuroenteric hormones in intestinal infectious diseases.

It is now well established that communication among the enteric nerves, hormones, and neuropeptides plays a role in the pathogenesis of infectious gastrointestinal conditions. The results of several studies suggest that enteric nerves and hormones modulate important gastrointestinal functions such as intestinal motility and transport, intestinal permeability, fluid secretion, and inflammation in response to infectious agents. During the past year several gut-brain peptides, including substance P, neurotensin, and galanin, emerged as important mediators in the development and progress of intestinal infectious conditions. The intestinal mechanism of neuropeptide and hormone action involves direct effects via binding to receptors on the intestinal epithelium as well as on immune cells localized underneath the epithelial layer. Based on the available evidence from whole animal models it is possible that these new paradigms may offer novel therapeutic strategies in the treatment of gastrointestinal infections. This review summarizes recent progress on the identification of peptide hormones participating in the pathophysiology of infectious intestinal conditions and discusses the possible mechanism(s) of action involved in these processes.