Interleukin-1[beta] in the dorsal vagal complex inhibits trh
analogue-induced stimulation of gastric contractility in rats.
Morrow, Nancy S., Gerardo Quinonez, Herbert Weiner, Yvette Tache, and
Thomas Garrick.
CURE\Gastroenteric Biology Center, Departments of Psychiatry,
Medicine and Research, Department of Veterans Affairs Medical Center,
West Los Angeles, Departments of Psychiatry and Biobehavioral
Sciences, Medicine, University of California, Los Angeles, CA
90024
APStracts 2:0039G, 1995.
The effect of murine IL-1[beta] (mIL-1[beta]) microinjected into the
dorsal vagal complex (DVC) on TRH analogue (RX 77368)-induced
stimulation of gastric contractility was examined in fasted,
urethane-anesthetized rats. Gastric corpus contractions were measured
with extraluminal force transducers and analyzed by computer.
Microinjection of RX 77368 (30 ng) into the right DVC with mIL
-1[beta] microinjected either into the right (100, 250 pg) or into the
left (100, 500 pg) DVC inhibited gastric contractility for 30-120
post-injection. Peak suppression of gastric contractility (64-78%)
occurred at 50-60 min postinjection. Microinjection of mIL-1[beta]
into the DVC at a lower dose (10 pg) or into adjacent sites to the
DVC (100-500 pg) did not suppress the stimulated gastric
contractility pattern. Injection of mIL-1[beta] (250 pg) or 0.1% BSA
into the DVC alone did not alter basal gastric contractility.
Intracisternal injection of the IL-1 receptor antagonist (250 ng/10
[mu]l) abolished the inhibitory effect of mIL-1[beta] (250 pg) on
gastric contractility. These results demonstrate that mIL-1[beta]
acts in the DVC to inhibit vagally stimulated gastric contractility
and its action is mediated by IL-1 receptors.
Received 1 June 1995; accepted in final form 22 February 1995.
APS Manuscript Number G209-4.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 21 March 1995.