生长抑素类似物SMS 201-995对人十二指肠基底外侧小泡ATP依赖性钙转运的影响。

Effect of the somatostatin analogue SMS 201-995 on ATP-dependent calcium transport of basolateral vesicles from human duodenum.

作者信息

Stoll R, Stern H, Schmidt H, Ruppin H, Domschke W

机构信息

Dept. of Medicine, University of Erlangen-Nuremberg, FRG.

出版信息

Scand J Gastroenterol. 1987 Dec;22(10):1200-4. doi: 10.3109/00365528708996464.

DOI:10.3109/00365528708996464

PMID:2893447

Abstract

Brush border membrane vesicles (BBMV) and basolateral membrane vesicles (BLMV) were simultaneously prepared from surgically resected pieces of morphologically intact human duodenum with a modified Percoll gradient centrifugation method. Alkaline phosphatase was enriched 20-fold in BBMV, whereas (Na+ + K+)-stimulated adenosine triphosphatase was enriched 15-fold in BLMV. BBMV and BLMV were preincubated with 3 microM synthetic somatostatin-14 or 3 microM SMS 201-995 for 10 min at 5 degrees C. In BBMV calcium, sodium, D-glucose, L-alanine, and D-mannitol uptake was unaffected by somatostatin-14 and SMS 201-995. In BLMV we found two Ca++ transport systems: Na+/Ca++ exchange and ATP-driven Ca++ transport. Somatostatin-14 had no effect on either of the two transport mechanisms. SMS 201-995 had no effect on Na+/Ca++ exchange but significantly inhibited basolateral ATP-dependent Ca++ transport (-40% +/- 5%, p less than 0.005).

摘要

采用改良的 Percoll 梯度离心法，从手术切除的形态完整的人十二指肠组织块中同时制备刷状缘膜囊泡（BBMV）和基底外侧膜囊泡（BLMV）。碱性磷酸酶在 BBMV 中富集了 20 倍，而（Na⁺ + K⁺）刺激的三磷酸腺苷酶在 BLMV 中富集了 15 倍。将 BBMV 和 BLMV 与 3 μM 的合成生长抑素 -14 或 3 μM 的 SMS 201 - 995 在 5℃下预孵育 10 分钟。在 BBMV 中，钙、钠、D - 葡萄糖、L - 丙氨酸和 D - 甘露醇的摄取不受生长抑素 -14 和 SMS 201 - 995 的影响。在 BLMV 中，我们发现了两种 Ca²⁺转运系统：Na⁺/Ca²⁺交换和 ATP 驱动的 Ca²⁺转运。生长抑素 -14 对这两种转运机制均无影响。SMS 201 - 995 对 Na⁺/Ca²⁺交换无影响，但显著抑制基底外侧 ATP 依赖性 Ca²⁺转运（-40% ± 5%，p ＜ 0.005）。