DIRECT RADIOIMMUNOASSAY OF HUMAN PROLACTIN IN SEMEN, SERUM AND URINE

Abstract

A sensitive assay method that will enable a simple and direct determination of urinary hPRL [human prolactin] without the need for pretreatment and which may lead to a simultaneous assay of semen, serum and urinary hPRL in 1 system was developed. In this way interassay errors are avoided. Intra-assay reproducibility was checked by 4 repeated determinations of the samples, and the SEM [standard error of the mean] did not exceed 11% of the mean value, while the SEM of the interassay reproducibility, as checked by 10 samples, reached 30% of the mean value. The sensitivity of the system was 0.2 ng. hPLR levels were 13.1 .+-. 1.1 (SEM) ng/ml in serum, 20.6 .+-. 3.0 ng/ml in semen and 1.3 .+-. 0.3 ng/ml in urine. hPRL values obtained by this modified assay confirm the values obtained by the NIH [National Institutes of Health] kit as per their procedure, but in the latter case the interassay spread was considerably bigger than in this assay. Semen hPRL levels are apparently about 1.6-fold higher than those of serum, while hPRL levels in urine are only about 1/10 of the serum values.