Journals of Gerontology Series A: Biological Sciences and Medical Sciences, Vol 50, Issue 3 M155-M161, Copyright © 1995 by The Gerontological Society of America
Effect of ileo-jejunal transposition on the growth of the GI tract and pancreas in young and aged rats
T Tsuchiya, J Ishizuka, K Sato, I Shimoda, S Rajaraman, T Uchida, CM Townsend Jr and JC Thompson
Tohoku University School of Medicine, Sendai, Japan.
BACKGROUND. Ileo-jejunal transposition (IJT; transposition of the distal
quarter of the small intestine into the proximal jejunum) is known to
stimulate mucosal growth of the transposed ileum, but the effects on other
parts of the small intestine are controversial. The effect of aging on the
trophic action of IJT is not known. METHODS. We examined the trophic effect
of IJT (3 weeks post-operation) on the gastrointestinal tract and pancreas,
and on plasma levels of neurotensin and gastrin in three different aged
groups of Fischer 344 rats (4, 12, and 24 months old). RESULTS. Three weeks
after IJT, the mucosal mass, villus height, and crypt depth increased
significantly in the transposed ileum as well as in the remainder of the
small intestine. The weights of the colon and pancreas increased
significantly after IJT. These responses were not affected by aging. In
each of the three age groups, IJT did not affect plasma gastrin level, but
significantly increased plasma level of neurotensin. CONCLUSIONS. The
distal ileum appears to play an important role in the regulation of growth
in the intestine and pancreas; this role is preserved in aged rats.
Neurotensin may play an important role in this mechanism.
