[生长抑素对离体壁细胞酸分泌抑制作用的机制]

[The mechanism of somatostatin-induced acid secretion inhibition in isolated parietal cells].

作者信息

Li X, Qian J, Chen Y, Chen Y

机构信息

Department of Gastroenterology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing 100730, China.

出版信息

Zhonghua Nei Ke Za Zhi. 2001 Apr;40(4):236-8.

PMID:11798583

Abstract

OBJECTIVE

So far five different somatostatin receptor(SSR) subtypes have been characterized. Somatostatin has been reported to inhibit acid secretion in vivo, but which subtype of the receptor mediate acid secretion in rabbit is unclear. The aim of this study is to identify which subtype mediates inhibition of acid secretion and to observe the effects of somatostatin and its selective agonists on histamine-stimulated acid secretion by(14)C-aminopyrine((14)C-AP) accumulation.

METHODS

The effect of SS-14 and other receptor subtype agonists on histamine-stimulated acid secretion was studied with(14)C-AP accumulation in pure parietal cells. To identify SSR on parietal cells, positive SSR-specific primers by reverse transcription polymerase chain reaction (RT-PCR) and its probe by in situ hybridization (ISH) were used.

RESULTS

(1) SS-14, sandostatin and SSR2 specific agonist NC8-12 (10(-9)-10(-7) mol/L) significantly inhibited histamine-stimulated (10(-6)) mol/L) acid secretion (P < 0.01), but SSR3 and SSR4 specific agonists had no inhibitory effects on histamine-stimulated acid secretion at the same concentrations(P > 0.05). (2) SSR2 gene expression in parietal cell was demonstrated with both RT-PCR and ISH method.

CONCLUSION

The authors verified for the first time that SSR2 mediates the inhibition of histamine-induced acid secretion in parietal cell, and that SSR2 is present on parietal cells.

摘要

目的

迄今为止，已鉴定出五种不同的生长抑素受体（SSR）亚型。据报道，生长抑素在体内可抑制胃酸分泌，但尚不清楚在兔体内哪种受体亚型介导胃酸分泌。本研究的目的是确定哪种亚型介导胃酸分泌的抑制作用，并通过¹⁴C-氨基比林（¹⁴C-AP）蓄积观察生长抑素及其选择性激动剂对组胺刺激的胃酸分泌的影响。

方法

采用¹⁴C-AP蓄积法，在纯壁细胞中研究SS-14和其他受体亚型激动剂对组胺刺激的胃酸分泌的影响。为了鉴定壁细胞上的SSR，采用逆转录聚合酶链反应（RT-PCR）的阳性SSR特异性引物及其原位杂交（ISH）探针。

结果

（1）SS-14、善得定和SSR2特异性激动剂NC8-12（10⁻⁹ - 10⁻⁷mol/L）显著抑制组胺刺激（10⁻⁶mol/L）的胃酸分泌（P < 0.01），但相同浓度下SSR3和SSR4特异性激动剂对组胺刺激的胃酸分泌无抑制作用（P > 0.05）。（2）采用RT-PCR和ISH方法均证实了壁细胞中有SSR2基因表达。