Rix E W, Feurle G E, Carraway R E
Histochemistry. 1986;85(2):135-8. doi: 10.1007/BF00491760.
Studies indicating evidence for the presence of the amphibian octapeptide xenopsin in gastric mucosa of mammals prompted us to investigate the cellular localization of this peptide. Using the peroxidase-antiperoxidase method and a specific antiserum to xenopsin (Xen-7) on paraffin and adjacent semithin sections of gastric antral mucosa from man, dog, and Tupaia belangeri, we found numerous epithelial cells showing a specific positive immunoreaction. These cells were of typical pyramidal shape and could be classified as of the "open" type. Cell quantification in serial sections processed for xenopsin and gastrin immunoreactivity, respectively, revealed an identical number of cells per section and an identical distribution of these cells in the middle zone of the antral mucosa. Furthermore, adjacent semithin sections demonstrated the colocalization of xenopsin and gastrin immunoreactivity within the same G-cell. The xenopsin antiserum could be completely absorbed with synthetic xenopsin but not with gastrin. Preabsorption tests with neurotensin, a xenopsin related peptide, or with somatostatin, glucagon, and enkephalins gave no evidence for crossreactivity of the xenopsin antiserum with these peptides. It is concluded that gastric antral G-cells in addition to gastrin also contain the amphibian peptide xenopsin.
多项研究表明，在哺乳动物胃黏膜中存在两栖类八肽爪蟾肽，这促使我们对该肽的细胞定位进行研究。我们采用过氧化物酶 - 抗过氧化物酶法，使用针对爪蟾肽（Xen - 7）的特异性抗血清，对人、狗和树鼩胃窦黏膜的石蜡切片及相邻半薄切片进行检测，发现大量上皮细胞呈现特异性阳性免疫反应。这些细胞呈典型的金字塔形，可归类为“开放”型。分别对经爪蟾肽和胃泌素免疫反应处理的连续切片进行细胞定量分析，结果显示每片切片中的细胞数量相同，且这些细胞在胃窦黏膜中间区域的分布也相同。此外，相邻的半薄切片显示爪蟾肽和胃泌素免疫反应在同一G细胞内共定位。爪蟾肽抗血清可被合成的爪蟾肽完全吸收，但不能被胃泌素吸收。用与爪蟾肽相关的神经降压素，或生长抑素、胰高血糖素和脑啡肽进行预吸收试验，未发现爪蟾肽抗血清与这些肽有交叉反应。由此得出结论，胃窦G细胞除了含有胃泌素外，还含有两栖类肽爪蟾肽。
