Preparation of biologically active radioiodinated cholecystokinin for radioreceptor assay and radioimmunoassay.
A modified method is described for the preparation of stable, high specific activity radioiodinated cholecystokinin (CCK) by its conjugation to 125I-Bolton Hunter reagent (125I-BH). Purified radioiodinated CCK (125I-BH-CCK) stimulated amylase release from isolate rat pancreatic acini with a potency identical to that of native CCK. Further, 125I-BH-CCK was highly immunoreactive and reacted with antisera directed toward both the NH2- and COOH-terminal portions of the CCK molecule. Finally, 125I-BH-CCK bound to specific receptor sites on isolated pancreatic acini.
D000818:Animals; D001667:Binding, Competitive; D002766:Cholecystokinin / Q000378:metabolism*; D007106:Immune Sera; D007457:Iodine Radioisotopes; D007553:Isotope Labeling / Q000379:methods; D007700:Kinetics; D008297:Male; D011863:Radioimmunoassay; D011869:Radioligand Assay; D051381:Rats; D011956:Receptors, Cell Surface / Q000378:metabolism*
D007106:Immune Sera; D007457:Iodine Radioisotopes; D011956:Receptors, Cell Surface; D002766:Cholecystokinin