Short-chain fatty acid receptor, GPR43, is expressed by enteroendocrine cells and mucosal mast cells in rat intestine
Short-chain fatty acid receptor, GPR43, is expressed by enteroendocrine cells and mucosal mast cells in rat intestine
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DOI：
10.1007/s00441-005-0140-x
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发表时间：
2006-06-01
影响因子：
3.6
通讯作者：
Kuwahara, A
中科院分区：
文献类型：
--
作者：
Karaki, S;Mitsui, R;Kuwahara, A
短链脂肪酸 (SCFA)，例如乙酸盐、丙酸盐和丁酸盐，是大肠腔中的主要阴离子。它们是通过细菌发酵由膳食纤维产生的，已知对肠道具有多种生理和病理生理作用。在本研究中，我们研究了 SCFA 受体 GPR43 在大鼠远端回肠和结肠中的表达。通过逆转录酶/聚合酶链反应（RT-PCR）、蛋白质印迹和免疫组织化学检测GPR43的表达。通过 RT-PCR，在回肠和结肠的整个壁和分离粘膜的提取物以及回肠的肌肉加粘膜下层的提取物中检测到 GPR43 的 mRNA，但在结肠的肌肉加粘膜下层制备物中未检测到。我们针对大鼠 GPR43 的合成片段制备了兔抗血清；这是大鼠 GPR43 特有的。通过蛋白质印迹分析，在全壁和分离的粘膜提取物中检测到 GPR43 蛋白，但在肌肉和粘膜下层提取物中未检测到。通过免疫组织化学，GPR43 免疫反应性局限于表达肽 YY (PYY) 的肠内分泌细胞，而 5-羟色胺 (5-HT) 免疫反应性 (IR) 肠内分泌细胞对 GPR43 没有免疫反应性。表达5-HT的固有层肥大细胞也是GPR43-IR。本研究的结果表明，含有 PYY 的肠内分泌细胞和含有 5-HT 的粘膜肥大细胞通过 GPR43 受体感知 SCFA。这与生理数据一致，表明 SCFA 刺激回肠和结肠释放 PYY 和 5-HT。
Short-chain fatty acids (SCFAs), such as acetate, propionate, and butyrate, are the major anions in the large intestinal lumen. They are produced from dietary fiber by bacterial fermentation and are known to have a variety of physiological and pathophysiological effects on the intestine. In the present study, we investigated the expression of the SCFA receptor, GPR43, in the rat distal ileum and colon. Expression of GPR43 was detected by reverse transcriptase/polymerase chain reaction (RT-PCR), Western blotting, and immunohistochemistry. mRNA for GPR43 was detected, by RT-PCR, in extracts of the whole wall and separated mucosa from the ileum and colon and from muscle plus submucosa from the ileum, but not from muscle plus submucosa preparations from the colon. We raised a rabbit antiserum against a synthesized fragment of rat GPR43; this was specific for rat GPR43. GPR43 protein was detected by Western blot analysis in extracts of whole wall and separated mucosa, but not in muscle plus submucosa extracts. By immunohistochemistry, GPR43 immunoreactivity was localized to enteroendocrine cells expressing peptide YY (PYY), whereas 5-hydroxytryptamine (5-HT)-immunoreactive (IR) enteroendocrine cells were not immunoreactive for GPR43. Mast cells of the lamina propria expressing 5-HT were also GPR43-IR. The results of the present study suggest that the PYY-containing enteroendocrine cells and 5-HT-containing mucosal mast cells sense SCFAs via the GPR43 receptor. This is consistent with physiological data showing that SCFAs stimulate the release of PYY and 5-HT from the ileum and colon.