Schwittlick U, Junginger J, Hahn K, Habierski A, Hewicker-Trautwein M
Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, D-30559, Hannover, Germany.
Anat Histol Embryol. 2017 Feb;46(1):33-42. doi: 10.1111/ahe.12229. Epub 2016 Feb 11.
Histamine is an important mediator of many physiological processes including gastrointestinal function that acts via four different histamine receptors (H1R to H4R). Elevated histamine levels and increased HR messenger ribonucleic acid (mRNA) have been shown in humans with gastrointestinal disorders such as irritable bowel syndrome or allergic intestinal diseases. As there is limited knowledge concerning the distribution of histamine receptors (HR) in dogs, one aim of this study was to investigate the expression of histamine 1 receptor (H1R), histamine 2 receptor (H2R) and histamine 4 receptor (H4R) in the canine gastrointestinal tract at protein level using immunohistochemistry. Histamine 1 receptor, H2R and H4R were widely expressed throughout the canine gastrointestinal tract including epithelial, mesenchymal, neuronal and immune cells. In addition, in situ hybridisation was established for detecting canine H4R mRNA. Results showed H4R mRNA to be present in enterocytes, lamina propria immune cells and submucosal plexus in the duodenum and colon of nearly all investigated animals. The results elucidate the importance of HR in the canine gut and represent the basis for investigating their possible impact on canine inflammatory gastrointestinal disorders.
组胺是许多生理过程的重要介质，包括通过四种不同的组胺受体（H1R至H4R）发挥作用的胃肠功能。在患有胃肠疾病（如肠易激综合征或过敏性肠道疾病）的人类中，已显示出血清组胺水平升高和组胺受体信使核糖核酸（mRNA）增加。由于关于犬类组胺受体（HR）分布的知识有限，本研究的一个目的是使用免疫组织化学在蛋白质水平上研究组胺1受体（H1R）、组胺2受体（H2R）和组胺4受体（H4R）在犬胃肠道中的表达。组胺1受体、H2R和H4R在犬胃肠道中广泛表达，包括上皮细胞、间充质细胞、神经元细胞和免疫细胞。此外，还建立了用于检测犬H4R mRNA的原位杂交技术。结果显示，几乎所有研究动物的十二指肠和结肠中的肠细胞、固有层免疫细胞和黏膜下神经丛中都存在H4R mRNA。这些结果阐明了HR在犬肠道中的重要性，并为研究它们对犬类炎症性胃肠疾病的可能影响奠定了基础。
