Laboratory of Cell Biology and Histology, Department of Veterinary Sciences, University of Antwerp, Belgium.
Histochem Cell Biol. 2011 Nov;136(5):569-85. doi: 10.1007/s00418-011-0862-7. Epub 2011 Sep 13.
The MAS-related gene (Mrg) receptor MrgE has been suggested to be expressed at all tissue levels involved in pain sensation and to influence the expression of another Mrg receptor, MrgF. Given the knowledge on the role of the enteric nervous system (ENS) in sensation, and the plasticity of enteric neurons during intestinal inflammation, it can be hypothesized that MrgE is expressed in enteric neurons, and that MrgE and MrgF change expression in intestinal inflammatory conditions. Therefore, we aimed to reveal the expression details of MrgE and MrgF in the murine ileum in normal and inflamed conditions. Using reverse transcriptase-PCR, quantitative-PCR and immunohistochemistry, we compared the ileum of non-inflamed control mice with that of two models of intestinal inflammation, i.e. intestinal schistosomiasis and chemically induced ileitis. MrgE and MrgF mRNAs were detected in control and inflamed conditions. MrgE and MrgF mRNAs showed a trend towards downregulation during intestinal schistosomiasis and a significant reduction during ileitis. MrgE and MrgF receptors were expressed in distinct enteric neuronal subpopulations, such as the sensory, secretomotor and vasodilator neurons, and in nerve fibres in the tunica muscularis and lamina propria of control and inflamed ileum. Only a minor proportion of enteric neurons co-expressed MrgE and MrgF. The number of enteric neurons expressing MrgE and MrgF receptors was significantly reduced during intestinal schistosomiasis and ileitis. This is the first report on the expression of MrgE and MrgF in the ENS in (patho)physiological conditions. The expression of MrgE and MrgF in enteric neurons was negatively affected by inflammation.
MAS 相关基因（Mrg）受体 MrgE 被认为在参与疼痛感觉的所有组织水平上表达，并影响另一种 Mrg 受体 MrgF 的表达。鉴于肠神经系统（ENS）在感觉中的作用以及肠神经元在肠道炎症期间的可塑性知识，可以假设 MrgE 在肠神经元中表达，并且 MrgE 和 MrgF 在肠道炎症条件下改变表达。因此，我们旨在揭示 MrgE 和 MrgF 在正常和炎症条件下在小鼠回肠中的表达细节。使用逆转录酶-PCR、定量-PCR 和免疫组织化学，我们比较了非炎症对照小鼠的回肠与两种肠道炎症模型，即肠道血吸虫病和化学诱导性回肠炎。在对照和炎症条件下检测到 MrgE 和 MrgF mRNAs。MrgE 和 MrgF mRNAs 在肠道血吸虫病期间呈下调趋势，在回肠炎期间显著减少。MrgE 和 MrgF 受体在不同的肠神经元亚群中表达，如感觉神经元、分泌运动神经元和血管扩张神经元，以及在对照和炎症回肠的肌层和固有层中的神经纤维中表达。只有一小部分肠神经元共表达 MrgE 和 MrgF。在肠道血吸虫病和回肠炎期间，表达 MrgE 和 MrgF 受体的肠神经元数量显著减少。这是第一个在（病理）生理条件下报告 MrgE 和 MrgF 在 ENS 中表达的报告。炎症对肠神经元中 MrgE 和 MrgF 的表达有负面影响。
