Vagal control of pyloric resistance.
Malbert, C. H., C. Mathis, and J. P. Laplace.
Equipe des flux digestifs, Station de Recherches Porcines INRA,
35590 Saint Gilles, France
APStracts 2:0073G, 1995.
Pyloric resistance is probably a major factor regulating gastric
emptying of liquids but its nervous control is unknown. The role of
efferent vagal pathways in pyloric resistance was evaluated in
thirteen anaesthetized pigs. Pyloric resistance was assessed by
simultaneous recording of gastropyloroduodenal motility and
transpyloric flow during gastric emptying of saline. Cervical
vagotomy suppressed all antral pressure events, increased the number
of pressure events localized at the pylorus (IPPW's) and decreased
the frequency of the flow pulses (p<0.05), without affecting either
pyloric resistance or the characteristics of flow pulses. Electrical
stimulation of the cervical and the thoracic vagi both decreased
pyloric resistance by about 60% and increased the stroke volume of
flow pulses (p<0.05). The reduced pyloric resistance was mainly
related to an alteration of the temporal relationship between flow
pulses and pyloric pressure events. These results indicate that vagal
efferents could provide inhibitory inputs to pyloric resistance. A
reduction in pyloric resistance contributes to the increased flow
rate observed during vagal stimulation.
Received 7 November 1994; accepted in final form 29 March 1995.
APS Manuscript Number G103-4.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 25 April 1995.