NEUROPEPTIDES IN INFLAMMATORY BOWEL-DISEASE - AN UPDATE

Extrinsic and intrinsic neurons of the gut contain multiple neuropepti des, which through complex interactions modulate mucosal defense, infl ammation, and repair in response to injury. Initial changes of the neu rovascular peptidergic system may represent normal protective mechanis ms against tissue injury, whereas subsequent alterations of neurovascu lar regulation may contribute to the pathogenesis and maintenance of t he inflammatory state. Multiple interactions between sensory neurons, the immune system and growth factors appear to exist, and then is also a marked plasticity of the neurovascular peptidergic system with chan ges in the synthesis, release, binding, and degradation of peptides du ring inflammatory processes. A delicate and closely regulated balance between proinflammatory (e.g., SP, VIP, NPY) and antiinflammatory neur opeptides (e.g., CGRP, somatostatin, bombesin) seems to exist in the g astrointestinal tract. Disturbances of this balance might contribute t o the pathophysiology of inflammatory bowel disease. In our overview, we will describe the results of studies in animal models of experiment al inflammation and focus on the potential insight they provide in und erstanding the pathophysiology of inflammatory conditions of the bowel such as IBD. Knowledge with respect to these regulatory systems might provide novel insights into the inflammatory process and potentially expand the available therapeutic approaches in the management of IBD.