Johnston C F, Shaw C, Ardill J E, Sloan J M, Buchanan K D
Department of Medicine, Queen's University of Belfast, Northern Ireland.
Histochemistry. 1988;90(2):161-4. doi: 10.1007/BF00500981.
The nature of xenopsin immunoreactivity in mammalian antral G-cells has been reassessed. Xenopsin immunostaining was most intense in human antral G-cells, present in those of the dog and pig and not detected in guinea pig or rat tissues. Rigorous specificity controls for ionic binding of immunoglobulins to antral G-cell granules indicated that this mechanism was not responsible for xenopsin immunostaining. Preincubation of the xenopsin antiserum with xenopsin, human gastrin 1-13 and gastrin 2-17 completely abolished immunostaining at similar molar concentrations. Gastrin 34 was ineffective at much higher concentrations. These results infer that xenopsin-immunoreactivity in antral G-cells resides in the N-terminal region of gastrin 17. Examination of the primary structures of xenopsin and the N-terminal regions of some mammalian gastrins reveals a hitherto unrecognized homology.
对哺乳动物胃窦G细胞中胃泌素原免疫反应性的性质进行了重新评估。胃泌素原免疫染色在人胃窦G细胞中最为强烈，在狗和猪的胃窦G细胞中存在，而在豚鼠或大鼠组织中未检测到。对免疫球蛋白与胃窦G细胞颗粒的离子结合进行的严格特异性对照表明，这种机制与胃泌素原免疫染色无关。用胃泌素原、人胃泌素1-13和胃泌素2-17对胃泌素原抗血清进行预孵育，在相似的摩尔浓度下完全消除了免疫染色。胃泌素34在高得多的浓度下无效。这些结果推断，胃窦G细胞中的胃泌素原免疫反应性存在于胃泌素17的N端区域。对胃泌素原和一些哺乳动物胃泌素N端区域的一级结构进行检查，发现了一种迄今未被认识的同源性。
