自发性高血压大鼠回肠上皮内的体内糖扩散

In vivo sugar diffusion in the ileal epithelium of spontaneously hypertensive rats.

作者信息

Mate A, Gómez-Amores L, Vázquez C M, Bolufer J

机构信息

Dept. of Physiology and Zoology, University of Seville, c/Tramontana s/n, Seville, Spain.

出版信息

Scand J Gastroenterol. 2003 Sep;38(9):967-71. doi: 10.1080/00365520310004993.

DOI:10.1080/00365520310004993

PMID:14531534

Abstract

BACKGROUND

D-glucose absorption, distinguishing between active and diffusive components, was studied in the ileum of spontaneously hypertensive rats (SHR) and their normotensive control Wistar-Kyoto (WKY) rats. Net water transport was also determined.

METHODS

A perfusion system in vivo with ileum loops was used, and experiments with phlorizin, phloretin and 2,4,6-triaminopyrimidine (TAP) were performed in order to discriminate between active and diffusive components and between transcellular and paracellular routes.

RESULTS

A significant decrease in total D-glucose absorption was found in SHR compared to WKY rats, this reduction being due to a lower SGLT1-mediated component. The effect was not compensated by the total diffusive component, since the phlorizin-insensitive D-glucose absorption did not significantly change between rat strains. However, the diffusive component of D-glucose transport was relatively more important in hypertensive than in normotensive rats. The use of 2,4,6-triaminopyrimidine (TAP), which blocks the transport across the paracellular route, showed that the paracellular diffusion of D-glucose was higher in SHR than in WKY rats. Intestinal net water absorption was not modified between either group of animals, though the presence of phlorizin in the perfusate decreased the ileal water absorption to a greater extent in normotensive rats.

CONCLUSION

The observed reduction in D-glucose absorption in vivo in the ileum of SHR was due to a decrease in the SGLT1-active component. Despite the paracellular diffusion of D-glucose being higher in hypertensive than in normotensive rats, the total diffusion component was not high enough to compensate this alteration.

摘要

背景

研究了自发性高血压大鼠（SHR）及其正常血压对照Wistar-Kyoto（WKY）大鼠回肠中D-葡萄糖的吸收情况，区分了主动吸收和扩散吸收成分。还测定了净水分转运。

方法

采用回肠肠袢体内灌注系统，进行了根皮苷、根皮素和2,4,6-三氨基嘧啶（TAP）实验，以区分主动吸收和扩散吸收成分以及跨细胞和细胞旁途径。

结果

与WKY大鼠相比，SHR的总D-葡萄糖吸收显著降低，这种降低是由于SGLT1介导的成分较低。由于根皮苷不敏感的D-葡萄糖吸收在不同品系大鼠之间没有显著变化，因此总扩散成分无法补偿这种影响。然而，D-葡萄糖转运的扩散成分在高血压大鼠中比正常血压大鼠中相对更重要。使用阻断细胞旁途径转运的2,4,6-三氨基嘧啶（TAP）表明，SHR中D-葡萄糖的细胞旁扩散高于WKY大鼠。两组动物的肠道净水分吸收均未改变，尽管灌注液中存在根皮苷时，正常血压大鼠的回肠水分吸收下降幅度更大。