Action of sensory neurons in an experimental rat colitis model of
injury and repair .
Reinshagen, M., A. Patel, M. Sottili, S. French, C. Sternini, and V.
E. Eysselein.
Inflammatory Bowel Disease Center, Harbor-UCLA Medical Center,
Torrance, CA 90509, Department of Pathology, Harbor-UCLA Medical
Center, Torrance, CA 90509, CURE/Digestive Disease Center, Department
of Medicine and Brain Research, Institute, UCLA School of Medicine
and VA Wadsworth Medical Center, Los Angeles, CA 90073
APStracts 2:0139G, 1995.
The influence of sensory nerves on inflammation and healing was
studied in a rat colitis model at different stages of inflammation.
Studies were performed in animals with and without ablation of
sensory nerves which was achieved by pretreatment with the neurotoxin
capsaicin. Colitis was induced by a rectal enema containing
trinitrobenzenesulfonic acid (TNB, 50 mg/kg) in 50 % ethanol.
Severity of inflammation was markedly increased 3 and 7 days after
induction of colitis in the capsaicin pretreated group compared to
the vehicle group as determined by a macroscopic damage score (MDS)
(at 3 days, 12.0 + 0.7 vs. 7.5 + 1.5; at 7 days, 12.2 + 0.8 vs. 6.5 +
0.8, p<0.05), by histology (ulceration score at 3 days, 82 + 12%
vs. 40 + 11%; at 7 days 92 + 5% vs. 46 + 13%, p<0.05) and by
myeloperoxidase activity (at 3 days, 133 + 30 vs. 42 + 14; at 7 days
76 + 11 vs. 39 + 11 U/mg protein, p<0.05). There was no
significant difference in the severity of colitis 14 and 21 days
after induction of colitis between the capsaicin pretreated group and
the vehicle group. These data suggest that in this model sensory
nerves have an important protective function in the acute and
subacute phases of inflammation, but do not seem to play a
significant role in the later stages of chronic inflammation.
Received 15 March 1993; accepted in final form 28 June 1995.
APS Manuscript Number G86-3.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 18 July 1995.