Rhythmic oscillating complexes in the gastrointestinal tract of
chickens: a role for motilin.
Rodr[acute]iguez-Sinovas, A., M. Jim[acute]enez, P. De Clercq, T. L.
Peeters, and P. Vergara.
Department of Cell Biology and Physiology, Veterinary Faculty,
Universitat Aut[grave]onoma de Barcelona, 08193 Bellaterra, Spain Gut
Hormone Laboratory. Katholieke Universiteit Leuven, Belgium
APStracts 3:0218G, 1996.
Rhythmic oscillating complex (ROC) is a highly organized
gastrointestinal motility pattern recently described in fasted avian
species. ROCs show several high-speed propagated aborad contractions
that progressively change into others of orad direction. In addition,
chickens show migrating motor complexes (MMC) both in fed and fasting
states. Recently, motilin was isolated and characterized from chicken
small intestine. Accordingly, the aim of this study was to check if
chicken motilin might be involved in either ROC or MMC induction.
Electromyographical recordings were obtained from different areas of
the gastrointestinal tract of chickens while motilin was infused. The
response to chicken motilin was dose-dependent both in fed and fasted
animals: a bolus of 4x10-11 moles/kg (n=5) did not modify the
intestinal motor pattern, whereas 4x10-10 and 4x10-9 moles/kg (n=5
each) induced a complete ROC pattern of 5.2+/-0.6 and 10.8+/-0.9
minutes respectively. Rhythmic oscillating complexes induced by
chicken motilin presented exactly the same pattern as that described
during a spontaneous ROC. Furthermore, motilin concentration in
plasma, measured by RIA, increased during a spontaneous ROC. This
study suggests that chicken motilin triggers a rhythmic oscillating
complex in chickens. The fact that plasma motilin levels increased
during spontaneous ROC strongly suggests that motilin is involved in
the induction of the ROC pattern. Motilin seems to play a different
role in avian and mammalian species since a phase III of the MMC was
never induced by motilin infusion.
Received 1 May 1996; accepted in final form 1 October 1996.
APS Manuscript Number G170-6.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 5 November 1996