Mr. Oliver et al., COLONIC AND JEJUNAL MOTOR DISTURBANCES AFTER COLONIC ANTIGEN CHALLENGE OF SENSITIZED RAT, Gastroenterology, 112(6), 1997, pp. 1996-2005
Background & Aims: Inflammation in the colon may alter motility in the
proximal gut and potentiate clinical symptoms, The aim of this study
was to characterize the effect of colonic anaphylaxis on local (coloni
c) and remote (small intestinal) motility and identify the mechanism a
nd mediators involved. Methods: Rats were sensitized by intraperitonea
l injection of 10 mu g egg albumin and surgically prepared with electr
odes in jejunum and colon and a colostomy tube. Colonic and jejunal my
oelectric activity were recorded in fasted animals before and after co
lonic antigen challenge without and then after pretreatment with speci
fic antagonists, Results: Colonic antigen challenge of sensitized rats
was associated with significant (1) increase in colonic myoelectric s
pike activity, (2) disruption of fasting jejunal motility and initiati
on of aborally propagating spike complexes, and (3) increase in plasma
rat mast cell protease II levels with a decrease in granulated mast c
ells in colon but not jejunum, The myoelectric disturbance in both col
on and jejunum was inhibited significantly by pretreatment with atropi
ne and hexamethonium, doxantrazole, cyclooxygenase, and lipoxygenase i
nhibitors. Methysergide inhibited only the jejunal disturbance, Conclu
sions: Colonic antigen challenge of sensitized animals results in loca
l mast cell activation and the release of mediators that modulate neur
al pathways to initiate both a local colonic and a remote jejunal myoe
lectric disturbance.