RADIOIMMUNOASSAY OF HUMAN PLASMA ACTH / 中华内分泌代谢杂志

ABSTRACT

Radioimmunoassay of human plasma ACTH was developed. Rabbit was immunized by a1-28 ACTH conjugated to BSA. A specific antiserum with an optimal dilution of 132,000-60,000 was obtained. The radioiodination of a1-28 ACTH was processed by chloramine-T oxidation-sodium metabisulfite method, and the radiochemical purity of 125I-a1-28 ACTH was about 90-95.5% . The sensitivity of the present assay was 4 pg/ml, with a range of 10-640 pg/ml. The intraassay coefficient of variation was 2.3-7.0% while the interassay coefficient of variation 8.5-8.8%.The concentration of human plasma ACTH was determined by this assay in 20 healthy adults, and the results ranged from 10-90 pg/ml at SAM. The levels of plasma ACTH showed apparent circadian periodicity. In five patients the results of plasma ACTH were consistent with their clinical diagnoses.