A simple enzymatic procedure for radioimmunochemical quantitation of the large molecular forms of gastrin and cholecystokinin

✍ Scribed by Laura de Magistris; Jens F. Rehfeld

• Book ID: 102983235
• Publisher: Elsevier Science
• Year: 1980
• Tongue: English
• Weight: 563 KB
• Volume: 102
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(80)90327-9

✦ Synopsis

We have developed a simple enzymatic procedure for evaluation of antisera reactivity against the large molecular forms of gastrin and cholecystokinin (CCK). The procedure can be used for radioimmunochemical quantitation of the precursor molecules. The different molecular forms of gastrin or CCK in tissue extracts or plasma were separated by gel chromatography. The concentration of each form was then measured with 17 different antisera before and after tryptic cleavage. The ratio between the molar concentrations before and after tryptic cleavage varied from 0.32 to 1.00. Such variation can explain the variable hormone concentrations in serum and tissue measured with different radioimmunoassays. The present procedure can be performed with any biological fluid containing the precursor forms. It does not require the large molecular forms in pure state. In principle the procedure can be used for quantitation of all peptide precursors.