Jensen S, Borch K, Hilsted L, Rehfeld J F
University Department of Clinical Chemistry, Rigshospitalet, Copenhagen, Denmark.
Gastroenterology. 1989 Apr;96(4):1063-70. doi: 10.1016/0016-5085(89)91624-7.
Using radioimmunoassays specific for essential processing sites of human progastrin in combination with chromatography before and after cleavage with trypsin and carboxypeptidase B, we have examined antral biopsy specimens and serum from 10 hypergastrinemic patients with fundic atrophic gastritis and 7 normal control subjects. Four types of processing were studied: N-terminal proteolysis (at the N-terminus of component I, gastrin 34, and gastrin 17); C-terminal proteolysis (at the C-terminus of the amide donor, glycine93 in preprogastrin); alpha-carboxyamidation (of phenylalanine92); and O-sulfation (of tyrosine87). The results show that progastrin during permanent G-cell hypersecretion is less completely processed with respect to C-terminal proteolysis, alpha-amidation, and tyrosine-sulfation. In contrast, the degree of N-terminal proteolysis is normal. Thus, the processing of progastrin adjacent to the active site of gastrin is more restrictively controlled than N-terminal processing during G-cell hypersecretion associated with pernicious anemia.
我们使用针对人胃泌素主要加工位点的放射免疫分析法，并结合胰蛋白酶和羧肽酶B切割前后的色谱法，检测了10例患有胃体萎缩性胃炎的高胃泌素血症患者的胃窦活检标本和血清，以及7名正常对照者的标本和血清。研究了四种加工类型：N端蛋白水解（在组分I、胃泌素34和胃泌素17的N端）；C端蛋白水解（在前胃泌素中酰胺供体甘氨酸93的C端）；α-羧基酰胺化（苯丙氨酸92的）；以及O-硫酸化（酪氨酸87的）。结果表明，在持续性G细胞分泌过多期间，胃泌素原在C端蛋白水解、α-酰胺化和酪氨酸硫酸化方面的加工不完全。相比之下，N端蛋白水解程度正常。因此，在与恶性贫血相关的G细胞分泌过多期间，胃泌素原活性位点附近的加工比N端加工受到更严格的控制。
