Abstract
The pleomorphism of follicle-stimulating hormone (FSH) in human serum was investigated by gel chromatography on Sephadex G-200 and zone electrophoresis in agarose suspension. The FSH activity was measured by radioimmunoassay. By gel chromatography FSH in sera from 3 males and 5 females of various ages was eluted within a narrow range after albumin and no sex hormone related pleomorphism was found. Electrophoresis in 0.17% agarose suspension was found to be a technique suitable for analysis of differences in charge of FSH in sera from men and women. A total of 31 sera from 25 individuals was investigated. The results strongly indicate that there is in man a sex hormone related pleomorphism of FSH with less acidic forms of FSH in sera of normal women of fertile age than in sera of men and post-menopausal women. Qualitative analysis of FSH in serum by electrophoresis may become an important complement to the quantitative determinations of the FSH concentration for the clinical diagnosis of reproductive disorders and of FSH producing tumours.