Tabata K, Johnson L R
Am J Physiol. 1986 Aug;251(2 Pt 1):G270-4. doi: 10.1152/ajpgi.1986.251.2.G270.
The purpose of this study was to examine the role of ornithine decarboxylase (ODC) in the stimulation of the growth of gastrointestinal mucosa following feeding. Rats were divided into five groups: 1) fasted for 2 days, 2) fasted for 2 days and refed for 2 days, 3) fasted for 2 days and refed with the addition of 5% difluoromethylornithine (DFMO) to the drinking water, 4) normally fed, and 5) normally fed plus 5% DFMO in the drinking water. In general the results show a significant dissociation between ODC activity and growth of gastrointestinal mucosa in response to feeding. In the gastric mucosa, growth was inhibited by fasting and DFMO and stimulated by feeding, but there were no significant changes in ODC activity in any of the five groups. In the ileum ODC activity increased dramatically in refed rats and was essentially eliminated in rats fed DFMO. DFMO, however, had no effect on mucosal growth in fed rats and only prevented part of the trophic response to refeeding. The results in the colon were much the same as in the ileum, except that DFMO prevented even less of the trophic response to refeeding, despite total inhibition of ODC. These data suggest that polyamines necessary for growth of gastrointestinal mucosa following feeding are not supplied by the rapid activation of mucosal ornithine decarboxylase.
本研究的目的是探讨鸟氨酸脱羧酶（ODC）在进食后刺激胃肠道黏膜生长中的作用。将大鼠分为五组：1）禁食2天；2）禁食2天，再喂食2天；3）禁食2天，再喂食，同时在饮水中添加5%二氟甲基鸟氨酸（DFMO）；4）正常喂食；5）正常喂食，同时在饮水中添加5% DFMO。总体而言，结果显示ODC活性与进食后胃肠道黏膜生长之间存在显著分离。在胃黏膜中，禁食和DFMO抑制生长，进食刺激生长，但五组中ODC活性均无显著变化。在回肠中，再喂食的大鼠ODC活性显著增加，而喂食DFMO的大鼠ODC活性基本消除。然而，DFMO对喂食大鼠的黏膜生长无影响，仅部分阻止了对再喂食的营养反应。结肠中的结果与回肠大致相同，只是DFMO对再喂食的营养反应的阻止作用更小，尽管ODC被完全抑制。这些数据表明，进食后胃肠道黏膜生长所需的多胺并非由黏膜鸟氨酸脱羧酶的快速激活提供。
