Chaves M, Smith M W, Williamson R C
Department of Surgery, University of Bristol.
Gut. 1987 Aug;28(8):981-7. doi: 10.1136/gut.28.8.981.
The ability of adapting ileal enterocytes to express different digestive enzymes in their brush border membranes was tested in young female Wistar rats (n = 72) receiving 60% proximal small bowel resection. In control rats with intestinal transection both neutral aminopeptidase and alpha-glucosidase activities were shown, by quantitative cytochemistry, to increase during enterocyte migration over the lower part of the villus; thereafter enzyme activities declined or remained approximately constant. Proximal enterectomy increased the amount of alpha-glucosidase but not neutral aminopeptidase activity appearing during early enterocyte development. Thymidine labelled autoradiography showed that the rate of enterocyte migration along the ileal villus nearly doubled after jejunal resection (19.3 v 11.1 microns/h). Nevertheless, the time taken for both peptidase and saccharidase activities to appear at maximal rates in the brush border membrane was diminished by about five hours. Thus ileal enterocytes adapt to proximal small bowel resection by selective increments in enzyme expression, findings that contradict the previous hypothesis of simple metabolic immaturity.
在接受60%近端小肠切除的年轻雌性Wistar大鼠（n = 72）中，测试了回肠肠上皮细胞在其刷状缘膜中表达不同消化酶的适应能力。通过定量细胞化学方法显示，在对照大鼠中，肠横断后，中性氨肽酶和α-葡萄糖苷酶活性在肠上皮细胞迁移至绒毛下部的过程中均增加；此后酶活性下降或保持大致恒定。近端肠切除术增加了早期肠上皮细胞发育过程中出现的α-葡萄糖苷酶量，但未增加中性氨肽酶活性。胸腺嘧啶标记的放射自显影显示，空肠切除术后回肠绒毛上肠上皮细胞的迁移速率几乎增加了一倍（19.3对11.1微米/小时）。然而，肽酶和糖苷酶活性在刷状缘膜中达到最大速率所需的时间缩短了约5小时。因此，回肠肠上皮细胞通过选择性增加酶表达来适应近端小肠切除，这一发现与先前关于单纯代谢不成熟的假设相矛盾。
