Desmond H, Dockray G J, Spurdens M
Regul Pept. 1985 Jun;11(2):133-42. doi: 10.1016/0167-0115(85)90073-4.
A radioimmunoassay has been developed using antibodies to a synthetic analogue of the C-terminal hexapeptide sequence of the porcine gastrin precursor. Boiling water extracts of porcine antral mucosa contained immunoreactive material that diluted in parallel with standard peptide. Concentrations of immunoreactivity were 5.5 +/- 0.8 nmol X g-1 (mean +/- S.E.M.) in antral mucosa and were closely similar to those of C-terminal heptadecapeptide gastrin immunoreactivity (5.0 +/- 0.6 nmol X g-1). Approximately 30-fold lower concentrations were found in porcine duodenum. A similar distribution was found in ferret, but human, rat and chicken antrum did not contain significant quantities of immunoreactivity. Gel filtration of porcine antral extracts on Sephadex G-50 revealed a single peak of immunoreactivity eluting in a similar position to G17, but on anion-exchange chromatography two peaks of immunoreactive material were separated. These also differed in their retention time on reverse phase HPLC. Both peptides are probably derived by tryptic cleavage at the C-terminus of porcine preprogastrin. No evidence was found to suggest that there are significant quantities of unprocessed preprogastrin in hog antral mucosa. The precise chemical difference between the two immunoreactive peptides identified here remains to be established; together, however, they provide specific markers for progastrin synthesis.
已开发出一种放射免疫分析法，该方法使用针对猪胃泌素前体C末端六肽序列合成类似物的抗体。猪胃窦黏膜的沸水提取物中含有免疫反应性物质，其稀释度与标准肽平行。胃窦黏膜中免疫反应性的浓度为5.5±0.8 nmol·g-1（平均值±标准误），与C末端十七肽胃泌素免疫反应性的浓度（5.0±0.6 nmol·g-1）非常相似。在猪十二指肠中发现的浓度约低30倍。在雪貂中发现了类似的分布，但人、大鼠和鸡的胃窦中不含大量免疫反应性物质。用葡聚糖凝胶G-50对猪胃窦提取物进行凝胶过滤，发现一个免疫反应性单峰，其洗脱位置与G17相似，但在阴离子交换色谱上，分离出两个免疫反应性物质峰。它们在反相高效液相色谱上的保留时间也不同。这两种肽可能都是由猪前胃泌素C末端的胰蛋白酶切割产生的。没有证据表明猪胃窦黏膜中有大量未加工的前胃泌素。此处鉴定出的两种免疫反应性肽之间的确切化学差异仍有待确定；然而，它们共同为胃泌素原的合成提供了特异性标记。
