Extrinsic surgical denervation ameliorates TNBS-induced colitis in rats

Neurogenic inflammation refers to an inflammatory reflex arc by sensory neurons which transmit nocious stimulus centrally and results in both pain perception and intense local inflammatory reaction. Specific neurons, receptors, and their respective neurotransmitters have been studied in numerous organ systems including the gastrointestinal tract. Neurogenic inflammation has been suggested to play a key role in the pathogenesis of inflammatory bowel disease. In this study, we studied the effect of surgical denervation of specific somatosensory neurons in a well-established animal model of colitis.

Adult male rats were underwent surgical denervation around the inferior mesenteric artery or sham operation. After ten days trinitrobenzene sulfonic acid (TNBS) or vehicle was administered by enema. Inflammation was assessed by, histological evaluation, macroscopic damage score, myeloperoxidase (MPO) activity, and substance P receptor immunoreactivity (SPRIR).

Compared with sham operation with TNBS administration, surgical denervation with TNBS administration suppressed the score in all of the inflammatory indices and had almost no signs of inflammation in histological evaluation.

Surgical denervation has a protective effect on TNBS-induced colitis in rats. Thus, sensory neurons play a key role in the pathogenesis of inflammation in this well-established model of acute colitis.