Höllt V, Przewlocki R, Herz A
Naunyn Schmiedebergs Arch Pharmacol. 1978 Jun;303(2):171-4. doi: 10.1007/BF00508064.
A sensitive radioimmunoassay for beta-endorphin is described. Antibodies against human beta-endorphin which exhibit a high avidity for the C-terminal of the peptide were raised in rabbits following the injection of thyroglobulin-coupled human beta-endorphin (betah-E) as immunogen. Methionine-enkephalin, alpha-, gamma-endorphine, as well as ACTH peptides did not cause interference in the radioimmunoassay. beta-Lipotropin, however, showed a 50% cross-reactivity. The sensitivity of the assay is 25 pg/0.5 ml tube volume for beta-endorphin. beta-Endorphin was extracted with a high recovery from the rat plasma using silicic acid and beta-endorphin levels as low as 100 pg/ml could be measured. Basal levels of beta-endorphin-like immunoreactivity in plasma of rats were about 400 pg/ml. beta-Endorphin levels in adrenalectomized rats and in animals chronically treated with the cortisol synthesis blocker metyrapone were found to be markedly increased (about 7-fold). Exposure of the rats to electrically induced footshocks caused a similar increase of immunoreactive beta-endorphin in plasma. A significant increase was also seen after insulin injection.
本文描述了一种用于检测β-内啡肽的灵敏放射免疫分析法。以甲状腺球蛋白偶联的人β-内啡肽（βh-E）作为免疫原，给家兔注射后，产生了对该肽C末端具有高亲和力的抗人β-内啡肽抗体。甲硫氨酸脑啡肽、α-、γ-内啡肽以及促肾上腺皮质激素肽在放射免疫分析中均不产生干扰。然而，β-促脂素显示出50%的交叉反应性。该分析方法对β-内啡肽的灵敏度为25 pg/0.5 ml管体积。使用硅酸从大鼠血浆中提取β-内啡肽，回收率很高，可测量低至100 pg/ml的β-内啡肽水平。大鼠血浆中β-内啡肽样免疫反应性的基础水平约为400 pg/ml。发现肾上腺切除的大鼠以及长期用皮质醇合成阻滞剂美替拉酮治疗的动物体内β-内啡肽水平显著升高（约7倍）。给大鼠施加电刺激足底的电击会导致血浆中免疫反应性β-内啡肽出现类似的升高。注射胰岛素后也观察到显著升高。
