Jansen J B, Lamers C B
Department of Gastroenterology and Hepatology, University Hospital Leiden, The Netherlands.
Peptides. 1987 Sep-Oct;8(5):801-5. doi: 10.1016/0196-9781(87)90062-3.
The present study was undertaken to characterize molecular forms of cholecystokinin (CCK) in human fat-stimulated plasma by Sephadex G50 column chromatography followed by radioimmunoassays employing 3 different region-specific antibodies. CCK was extracted and concentrated from plasma of healthy subjects by adsorption to SEP-PAK C18 cartridges and from plasma of gastrectomized patients by addition of 96% ethanol. Antibody 1703 binds to carboxy-terminal CCK-peptides containing at least 14 amino acid residues, antibody T204 to sulfated carboxy-terminal CCK-peptides and antibody 5135 to carboxy-terminal forms of CCK and gastrin. Four molecular forms of CCK were consistently demonstrated; peak I eluted in the void volume and comprised 1.8-10.2% of CCK-immunoreactivity, peak II eluted between the void volume and the CCK-33/39 standard and comprised 9.8-21.6%, peak III eluted at the position of the CCK-33/39 standard and comprised 42.4-55.4%, and peak IV eluted between the CCK-33/39 and CCK-14 standards and comprised 25.4-40.1% of CCK immunoreactivity. Since these 4 molecular forms reacted to all 3 CCK-antibodies it is likely that they contain the sulfated tyrosyl and carboxy-terminal regions of CCK and, therefore, possess biological activity.
本研究旨在通过葡聚糖凝胶G50柱色谱法，随后采用3种不同的区域特异性抗体进行放射免疫测定，来表征人脂肪刺激血浆中胆囊收缩素（CCK）的分子形式。通过吸附到SEP-PAK C18柱上从健康受试者的血浆中提取并浓缩CCK，通过添加96%乙醇从胃切除患者的血浆中提取并浓缩CCK。抗体1703与含有至少14个氨基酸残基的羧基末端CCK肽结合，抗体T204与硫酸化的羧基末端CCK肽结合，抗体5135与CCK和胃泌素的羧基末端形式结合。一致证明了CCK的四种分子形式；峰I在空体积处洗脱，占CCK免疫反应性的1.8 - 10.2%，峰II在空体积和CCK - 33/39标准品之间洗脱，占9.8 - 21.6%，峰III在CCK - 33/39标准品的位置洗脱，占42.4 - 55.4%，峰IV在CCK - 33/39和CCK - 14标准品之间洗脱，占CCK免疫反应性的25.4 - 40.1%。由于这四种分子形式与所有三种CCK抗体都有反应，所以它们可能含有CCK的硫酸化酪氨酰和羧基末端区域，因此具有生物活性。
