Tsuchiya T, Ishizuka J, Sato K, Shimoda I, Rajaraman S, Uchida T, Townsend C M, Thompson J C
Tohoku University School of Medicine, Sendai, Japan.
J Gerontol A Biol Sci Med Sci. 1995 May;50(3):M155-61. doi: 10.1093/gerona/50a.3.m155.
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.
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).
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.
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.
回肠-空肠转位术（IJT；将小肠远端四分之一段转位至空肠近端）已知可刺激转位回肠的黏膜生长，但对小肠其他部位的影响存在争议。衰老对IJT营养作用的影响尚不清楚。
我们在三组不同年龄的Fischer 344大鼠（4、12和24月龄）中，研究了IJT术后3周对胃肠道和胰腺的营养作用，以及对神经降压素和胃泌素血浆水平的影响。
IJT术后3周，转位回肠以及小肠其余部分的黏膜质量、绒毛高度和隐窝深度均显著增加。IJT术后结肠和胰腺重量显著增加。这些反应不受衰老影响。在三个年龄组中，IJT均不影响血浆胃泌素水平，但显著提高了血浆神经降压素水平。
远端回肠似乎在肠道和胰腺生长调节中起重要作用；这一作用在老年大鼠中得以保留。神经降压素可能在此机制中起重要作用。
