Counter-regulation of the ileal motility in rabbit small intestine

370 Pages·1993·11.3 MB·English

by  Ferzoco, Stephen John

YALE
UNIVERSITY
CUSHING/WHITNEY
MEDICAL LIBRARY

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https://archive.org/details/counterregulatioOOferz

COUNTER-REGULATION OF
ILEAL MOTILITY IN RABBIT
SMALL INTESTINE
A Thesis Submitted to the Yale University School of Medicine
in partial fulfillment of the requirements for the Degree of
Doctor of Medicine
by
Stephen John Ferzoco
.
I ( 4
1993
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COUNTER-REGULATION OF ILEAL MOTILITY IN RABBIT SMALL
INTESTINE. Stephen J. Ferzoco. Department of Surgery, Yale
University School of Medicine, New Haven, CT.
Disorders of intestinal motility continue to plague
surgeons of the twentieth century. Unfortunately, the
regulation of intestinal motility remains incompletely
understood. Utilizing the isolated whole organ perfusion
system, segments of rabbit terminal ileum were infused with
variety of known gastrointestinal hormones, peptides and
neurotransmitters. In the first series of experiments,
prokinetic agents such as carbachol (an acetylcholine
analogue), cholecystokinin, motilin and were tested. All
three agents caused a concentration-dependent increase in
measured motor activity. In the second series of
experiments, agents which increase intracellular levels of
cAMP, vasoactive intestinal peptide (VIP), forskolin and
norepinephrine, were tested against prokinetic-stimulated
segments of ileum. All three agents caused a concentration-
dependent inhibition of motility. In the third series of
experiments, neuropeptide Y (NPY) and peptide YY (PYY),
agents which block intracellular cAMP, reversed the
inhibitory action of VIP. In the final series of
experiments, various NPY/PYY analogues with specific Y
receptor affinity were tested. The Yx receptor analogue
.
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