Non-neuronal dopamine in the gastrointestinal system.
Non-neuronal dopamine in the gastrointestinal system.
复制标题
DOI：
--
复制
发表时间：
1999-04
期刊：
影响因子：
--
通讯作者：
Eva Mezey;Graeme Eisenhofer;Stefan R. Hansson;G. Harta;Beth J. Hoffman;K. Gallatz;M. Palkovits
中科院分区：
文献类型：
--
作者：
Eva Mezey;Graeme Eisenhofer;Stefan R. Hansson;G. Harta;Beth J. Hoffman;K. Gallatz;M. Palkovits
1.多巴胺（DA）是大鼠和人类胃肠道（GI）的保护剂。因此，我们研究了DA生产的网站在大鼠和人类胃肠道使用各种技术，包括免疫细胞化学（ICC），原位杂交组织化学，逆转录聚合酶链反应，HPLC，蛋白质印迹和免疫电镜。2.我们发现非常高浓度的DA，持续化学交感神经切除术（CS）后，在胃液，胃粘膜和胰腺。胃粘膜和胰腺也有酪氨酸羟化酶（TH）的活性，其中大部分保留后CS。ICC双标记显示，产酸壁细胞和外分泌胰腺也必须能够产生DA。我们分离大鼠胃壁细胞的细胞分离，发现DA和TH活性存在于孤立的（去神经支配）壁细胞。这些细胞还具有胺能细胞的其他特征：它们对DA质膜转运蛋白和囊泡单胺转运蛋白呈免疫（和mRNA）阳性。在胃和十二指肠粘膜中，我们证明了大量的D5受体的存在，可以作为局部产生DA的靶点。由于DA，其生物合成酶和转运蛋白也存在于人胃壁细胞中，因此涉及DA的粘膜保护系统在临床上可能是重要的。
1. Dopamine (DA) is a protective agent in the gastrointestinal (GI) tract in both rats and humans. Therefore, we have studied the site of DA production in rat and human GI tract using a variety of techniques, including immunocytochemistry (ICC), in situ hybridization histochemistry, reverse transcription-polymerase chain reaction, HPLC, western blotting and immunoelectron microscopy. 2. We found very high concentrations of DA that persisted after chemical sympathectomy (CS) in the gastric juice, the stomach mucosa and in the pancreas. Both the stomach mucosa and the pancreas also had tyrosine hydroxylase (TH) activity, most of which remained after CS. Double-labelling ICC showed that acid-producing parietal cells and the exocrine pancreas must also be capable of producing DA. 3. We isolated rat stomach parietal cells by cell fractionation and found that both DA and TH activity are present in isolated (denervated) parietal cells. These cells also have other features of aminergic cells: they are immuno- (and mRNA) positive for the DA plasma membrane transporter and vesicular monoamine transporter(s). In both gastric and duodenal mucosa, we demonstrated the presence of significant amounts of the D5 receptor that could serve as a target for locally produced DA. 4. Because DA, its biosynthetic enzymes and its transporters are also found in parietal cells in the human stomach, a mucosal protective system involving DA could be important clinically.