Abstract
Two site immunoradiometric assay for human prolactin was developed by using 2 highly specific monoclonal antibodies. Although the procedure is simple one step sandwich assay with 3 hours of incubation time, there was no high-dose hook effect up to 84 μg/ml of prolactin. The intra- and interassay precision (CV%) were less than 6.4% ranging from 8.0 to 161 ng/ml and less than 3.4% ranging from 6.2 to 171 ng/ml, respectively. The good accuracy was also confirmed by recovery study (98.5±4.9%) and the good linearity on dilution study.
The assay presented here showed a good correlation with a commercially avarable kit but 3 of 16 patients with hyperprolactinemia showed higher prolactin levels measured by the presented assay than by a commercial kit. From the results of Sephadex G-100 gel chromatography, the discrepancy of prolactin levels in those three patients could be explained by the increase of big-big and/or big prolactin.
