Kummerlen C, Seiler N, Galluser M, Gossé F, Knodgen B, Hasselmann M, Raul F
Unité de Biologie Cellulaire et Physiopathologie Digestive, INSERM U61, Strasbourg, France.
Digestion. 1994;55(3):168-74. doi: 10.1159/000201143.
We have followed the time-course of the morphological and functional recovery of intestinal mucosa after 90 min of mesenteric vascular occlusion. At the end of the ischemic period the villi were smashed, but crypts were preserved. Microvillous hydrolase activities showed a dramatic drop when compared with sham-operated controls. Reperfusion was followed by an immediate upsurge of ornithine decarboxylase activity and a significant (p < 0.01) enhancement of putrescine and N1-acetyl-spermidine concentrations, while spermidine and spermine concentrations in mucosal cells decreased. This indicated that, both, de novo synthesis and degradation rates of the polyamines were increased. Treatment with alpha-difluoromethyl-ornithine, a selective inactivator of ornithine decarboxylase prevented the accumulation of active enzyme, but did not prevent morphological healing. It delayed however the recovery of sucrase and aminopeptidase-specific activities. Our results suggest that in addition to de novo synthesis, other sources of polyamines are mobilized to an extent that growth at a normal rate is supported. This indicates that the presence of active ornithine decarboxylase enzyme is not a prerequisite for the restitution of intestinal integrity after ischemia. We suggest that in a situation of inadequate polyamine supply the restoration of vital processes (mucosal regeneration) has priority over the restoration of specific functions.
我们跟踪观察了肠系膜血管闭塞90分钟后肠黏膜形态和功能恢复的时间进程。在缺血期末，绒毛遭到破坏，但隐窝得以保留。与假手术对照组相比，微绒毛水解酶活性显著下降。再灌注后，鸟氨酸脱羧酶活性立即激增，腐胺和N1 - 乙酰亚精胺浓度显著升高（p < 0.01），而黏膜细胞中亚精胺和精胺浓度降低。这表明多胺的从头合成和降解速率均增加。用α - 二氟甲基鸟氨酸（一种鸟氨酸脱羧酶的选择性灭活剂）处理可防止活性酶的积累，但不能防止形态学愈合。然而，它延迟了蔗糖酶和氨肽酶特异性活性的恢复。我们的结果表明，除了从头合成外，多胺的其他来源也被调动起来，以支持正常速度的生长。这表明活性鸟氨酸脱羧酶的存在不是缺血后肠完整性恢复的先决条件。我们认为，在多胺供应不足的情况下，生命过程（黏膜再生）的恢复优先于特定功能的恢复。
