Fahrenkrug J, Schaffalitzky de Muckadell O V
J Lab Clin Med. 1977 Jun;89(6):1379-88.
A sensitive and specific radioimmunoassay for vasoactive intestinal polypeptide (VIP) has been developed, which can detect 3.3 pmol x L-1 of the peptide in plasma. Antisera to highly purified porcine VIP coupled to albumin were raised in eight rabbits. The final dilution, the avidity, and the specificity of each antiserum were determined. 125I-VIP served as label, and highly purified porcine VIP was used as standard. Separtation of antibody-bound and free VIP was achieved by plasma-coated charcoal. Nonspecific interference withe assay system was excluded by extraction of plasma samples with ethanol. The reliability of the assay was investigated by recovery experiments, by serial dilution of plasma samples with high concentration of endogenous VIP, and by immunosorption. The within-and between assay reproducibility at a concentration of 18.3 pmol x L-1 was 1.6 and 2.3 pmol x L-1 (1 S.D.), respectively. Median fasting concentration of VIP in plasma from 74 normal subjects was 7.3 pmol x L-1 (range: 0-20.0 pmol x L-1).
已开发出一种用于检测血管活性肠肽（VIP）的灵敏且特异的放射免疫分析法，该方法可检测血浆中3.3 pmol×L-1的该肽。用与白蛋白偶联的高度纯化的猪VIP对8只兔子进行免疫，制备抗血清。测定了每种抗血清的最终稀释度、亲和力和特异性。以125I-VIP作为标记物，高度纯化的猪VIP作为标准品。采用血浆包被活性炭法分离抗体结合型和游离型VIP。通过用乙醇提取血浆样本排除了检测系统的非特异性干扰。通过回收率实验、对高浓度内源性VIP的血浆样本进行系列稀释以及免疫吸附实验研究了该检测方法的可靠性。在浓度为18.3 pmol×L-1时，该检测方法的批内和批间重复性分别为1.6和2.3 pmol×L-1（1个标准差）。74名正常受试者血浆中VIP的空腹浓度中位数为7.3 pmol×L-1（范围：0 - 20.0 pmol×L-1）。
