Zhao Hong, Bian Xiaochun, Galligan James J, Swain Greg M
Department of Chemistry and the Neuroscience Program, Michigan State University, East Lansing, MI 48824, USA.
Diam Relat Mater. 2010 Feb;19(2-3):182-185. doi: 10.1016/j.diamond.2009.10.004.
Irritable bowel syndrome (IBS) is a common gastrointestinal (GI) disorder characterized by chronic abdominal discomfort, including pain, bloating and changes in bowel habits. The exact cause of IBS is not entirely understood. Recent studies have shown that IBS may be associated with altered serotonin (5-hydroxytryptamine, 5-HT) levels within the GI tract. About 90% of 5-HT in the human body is produced and stored in enterochromaffin (EC) cells that reside in the mucosal layer of the intestine. Measurements of serotonin availability locally in the mucosa can provide insight on the functionality of these cells and potentially the pathophysiology of the disease. In this study, we used continuous amperometry with a diamond microelectrode to record serotonin levels in vitro in the ileum mucosa as an oxidation current. The boron-doped diamond (BDD) microelectrode is quite practical for these measurements because if its low background signal, low sensitivity to solution pH changes, and excellent resistance to fouling by adsorbed serotonin oxidation reaction products. In fact, the measurements are only possible because of the unique properties of diamond. We present electrochemical data that demonstrate the diamond microelectrode's utility for assessment of enterochromaffin cell function. Confirmation that the oxidation current was associated with indogenous serotonin release came from pharmacological studies. We are hopeful that these types of in vitro electrochemical measurements will lead to a better understanding of the pathophysiology of IBS.
肠易激综合征（IBS）是一种常见的胃肠道疾病，其特征为慢性腹部不适，包括疼痛、腹胀及排便习惯改变。IBS的确切病因尚未完全明确。近期研究表明，IBS可能与胃肠道内血清素（5-羟色胺，5-HT）水平改变有关。人体内约90%的5-HT由位于肠道黏膜层的肠嗜铬（EC）细胞产生并储存。对黏膜局部血清素可用性的测量能够深入了解这些细胞的功能以及该疾病潜在的病理生理学机制。在本研究中，我们使用带有金刚石微电极的连续安培法，以氧化电流形式记录回肠黏膜体外血清素水平。硼掺杂金刚石（BDD）微电极对于这些测量非常实用，因为它具有低背景信号、对溶液pH变化低敏感性以及对吸附的血清素氧化反应产物污染具有出色抗性。事实上，正是由于金刚石的独特性质才使得这些测量成为可能。我们展示的电化学数据证明了金刚石微电极在评估肠嗜铬细胞功能方面的实用性。氧化电流与内源性血清素释放相关这一结论来自药理学研究。我们希望这类体外电化学测量将有助于更好地理解IBS的病理生理学机制。
